diff --git a/.gitignore b/.gitignore
index 14ed0260..cc8c68f9 100644
--- a/.gitignore
+++ b/.gitignore
@@ -6,8 +6,10 @@
 scripts/*.sh
 # exclude
 vmms/id_rsa*
+vmms/id_ed25519*
 courselabs/*
 dockerTmp/*
+
 # config
 config.py
 
@@ -27,3 +29,10 @@ pip-selfcheck.json
 
 # Backup files
 *.bak
+
+# Redis
+*.rdb
+
+# Tests
+tests/*
+!tests/*.py
diff --git a/Dockerfile b/Dockerfile
index c120e15f..1fd31c81 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -32,13 +32,25 @@ RUN apt-get update && apt-get install -y \
 	ca-certificates \
 	lxc \
 	iptables \
+	iputils-ping \
  && apt-get clean \
  && rm -rf /var/lib/apt/lists/*
 
 WORKDIR /opt/TangoService/Tango/
 
-# Install Docker from Docker Inc. repositories.
-RUN curl -sSL https://get.docker.com/ -o get_docker.sh && sh get_docker.sh
+# Install Docker
+RUN set -eux; \
+    apt-get update; \
+    DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends ca-certificates curl gnupg; \
+    install -m 0755 -d /etc/apt/keyrings; \
+    curl -fsSL https://download.docker.com/linux/ubuntu/gpg -o /etc/apt/keyrings/docker.asc; \
+    chmod a+r /etc/apt/keyrings/docker.asc; \
+    . /etc/os-release; \
+    echo "deb [arch=$(dpkg --print-architecture) signed-by=/etc/apt/keyrings/docker.asc] https://download.docker.com/linux/ubuntu ${VERSION_CODENAME} stable" > /etc/apt/sources.list.d/docker.list; \
+    apt-get update; \
+    DEBIAN_FRONTEND=noninteractive apt-get install -y --no-install-recommends \
+      docker-ce docker-ce-cli containerd.io docker-buildx-plugin docker-compose-plugin; \
+    apt-get clean; rm -rf /var/lib/apt/lists/*
 
 # Install the magic wrapper.
 ADD ./wrapdocker /usr/local/bin/wrapdocker
@@ -69,6 +81,7 @@ RUN mkdir -p /var/log/docker /var/log/supervisor
 # Move custom config file to proper location
 RUN cp /opt/TangoService/Tango/deployment/config/nginx.conf /etc/nginx/nginx.conf
 RUN cp /opt/TangoService/Tango/deployment/config/supervisord.conf /etc/supervisor/supervisord.conf
+RUN if [ -f /opt/TangoService/Tango/boto.cfg ]; then cp /opt/TangoService/Tango/boto.cfg ~/.boto; fi
 
 # Reload new config scripts
 CMD ["/usr/bin/supervisord", "-c", "/etc/supervisor/supervisord.conf"]
diff --git a/README.md b/README.md
index d6bcb348..2da007a5 100644
--- a/README.md
+++ b/README.md
@@ -2,8 +2,7 @@
   <img src="images/autolab_banner.svg" width="380px" height="100px">
 </a>
 
-Tango
-======
+# Tango
 
 Tango is a standalone RESTful Web service that runs and manages jobs. A job is a set of files that must satisfy the following constraints:
 
@@ -16,13 +15,13 @@ Upon receiving a job, Tango will copy all of the job's input files into a VM, ru
 
 A brief overview of the Tango respository:
 
-* `tango.py` - Main tango server
-* `jobQueue.py` - Manages the job queue
-* `jobManager.py` - Assigns jobs to free VMs
-* `worker.py` - Shepherds a job through its execution
-* `preallocator.py` - Manages pools of VMs
-* `vmms/` - VMMS library implementations
-* `restful_tango/` - HTTP server layer on the main Tango
+- `tango.py` - Main tango server
+- `jobQueue.py` - Manages the job queue
+- `jobManager.py` - Assigns jobs to free VMs
+- `worker.py` - Shepherds a job through its execution
+- `preallocator.py` - Manages pools of VMs
+- `vmms/` - VMMS library implementations
+- `restful_tango/` - HTTP server layer on the main Tango
 
 Tango was developed as a distributed grading system for [Autolab](https://github.com/autolab/Autolab) at Carnegie Mellon University and has been extensively used for autograding programming assignments in CMU courses.
 
@@ -35,7 +34,63 @@ Please feel free to use Tango at your school/organization. If you run into any p
 3. [Read the documentation for the VMMS API](https://docs.autolabproject.com/tango-vmms/).
 4. [Test whether Tango is set up properly and can process jobs](https://docs.autolabproject.com/tango-cli/).
 
+## Stress Testing Tango
+
+To stress test Tango by running a large number of submissions, use `stressTest.py`. Currently, this is not a feature on the master branch. To use this feature, go on the `copy-in`.
+
+### Setting up the testing directory
+
+Create your testing directory by copying the 　`sample_test` directory into the `my_tests` directory.
+
+```
+cp -r sample_tests my_tests/<Test Name>
+```
+
+A brief overview of the testing directory
+
+- `input` - Directory to put your input files
+- `output` - Directory for the autograder output for each of the test submissions
+- `<Test Name>.yaml` - Yaml file to configure the stress test
+- `expected_output.txt` - Expected JSON output of the autograder
+- `summary.txt` - Summary of the autograder outputs
+- `log.txt` - Log of the submissions
+
+First, rename the `sample_test.yaml` to be `<Test Name>.yaml`
+
+```
+mv sample_test.yaml <Test Name>.yaml
+```
+
+Next, update the Yaml file.
+
+```yaml
+num_submissions: 5
+submission_delay: 0.1
+autograder_image: <Autograding Image>
+output_file: log.txt
+tango_port: 3001
+cli_path: <Path to Tango>/clients/tango-cli.py
+instance_type: <Instance Type>
+timeout: 180
+ec2: True
+expected_output: expected_output.txt
+stop_before:
+```
+
+After creating the Yaml file, copy the `autograde-Makefile`, `autograde.tar` and the file to submit in the `input` directory.
+
+### Running the stress test
+
+```
+virtualenv env
+source env/bin/activate
+pip install -r requirements.txt
+cd <Path to Tango>/tests
+python3 stressTest.py --test_dir my_tests/<Test Name>
+```
+
 ## Python 2 Support
+
 Tango now runs on Python 3. However, there is a legacy branch [master-python2](https://github.com/autolab/Tango/tree/master-python2) which is a snapshot of the last Python 2 Tango commit for legacy reasons. You are strongly encouraged to upgrade to the current Python 3 version of Tango if you are still on the Python 2 version, as future enhancements and bug fixes will be focused on the current master.
 
 We will not be backporting new features from `master` to `master-python2`.
diff --git a/clients/tango-cli.py b/clients/tango-cli.py
index 83dd12ce..701e66cd 100755
--- a/clients/tango-cli.py
+++ b/clients/tango-cli.py
@@ -12,10 +12,45 @@
 import argparse
 import sys
 import os
+from dataclasses import dataclass, asdict
+from typing import Optional
 
 sys.path.append("/usr/lib/python2.7/site-packages/")
 
 
+def get_arg(name, default=None):
+    """Helper function to safely get arguments using dictionary .get() method"""
+    if not hasattr(args, name):
+        raise KeyError(f"Argument '{name}' not found in args")
+    return vars(args).get(name, default)
+
+
+@dataclass
+class RequestObj:
+    """Dataclass for job request objects"""
+    image: str
+    files: str
+    timeout: int
+    max_kb: int
+    output_file: str
+    jobName: str
+    accessKeyId: str
+    accessKey: str
+    disable_network: bool
+    instanceType: str
+    stopBefore: str
+    notifyURL: Optional[str] = None
+    callback_url: Optional[str] = None
+
+
+@dataclass
+class VmObj:
+    """Dataclass for VM allocation objects"""
+    vmms: str
+    cores: int
+    memory: int
+
+
 #
 #
 # Set up the command line parser
@@ -71,11 +106,6 @@
 parser.add_argument("--runJob", help="Run a job from a specific directory")
 parser.add_argument("--numJobs", type=int, default=1, help="Number of jobs to run")
 
-parser.add_argument(
-    "--vmms",
-    default="localDocker",
-    help="Choose vmms between ec2SSH, tashiSSH, localDocker, and distDocker",
-)
 parser.add_argument(
     "--image", default="", help='VM image name (default "autograding_image")'
 )
@@ -116,6 +146,10 @@
     "--notifyURL",
     help="Complete URL for Tango to give callback to once job is complete.",
 )
+parser.add_argument(
+    "--callbackURL",
+    help="Complete URL for Tango to give callback to once job is complete.",
+)
 parser.add_argument(
     "--disableNetwork",
     action="store_true",
@@ -127,45 +161,45 @@
 parser.add_argument("--accessKeyId", default="", help="AWS account access key ID")
 parser.add_argument("--accessKey", default="", help="AWS account access key content")
 parser.add_argument("--instanceType", default="", help="AWS EC2 instance type")
-
+parser.add_argument("--stopBefore", default="", help="Stops the worker before a function is executed")
 
 def checkKey():
-    if args.key is None:
+    if get_arg('key') is None:
         print("Key must be specified with -k")
         return -1
     return 0
 
 
 def checkCourselab():
-    if args.courselab is None:
+    if get_arg('courselab') is None:
         print("Courselab must be specified with -l")
         return -1
     return 0
 
 
 def checkFilename():
-    if args.filename is None:
+    if get_arg('filename') is None:
         print("Filename must be specified with --filename")
         return -1
     return 0
 
 
 def checkInfiles():
-    if args.infiles is None:
+    if get_arg('infiles') is None:
         print("Input files must be specified with --infiles")
         return -1
     return 0
 
 
 def checkDeadjobs():
-    if args.deadJobs is None:
+    if get_arg('deadJobs') is None:
         print("Deadjobs must be specified with --deadJobs")
         return -1
     return 0
 
 
 def checkImageName():
-    if args.imageName is None:
+    if get_arg('imageName') is None:
         print("Image name must be specified with --imageName")
         return -1
     return 0
@@ -184,18 +218,18 @@ def tango_open():
 
         response = requests.get(
             "%s://%s:%d/open/%s/%s/"
-            % (_tango_protocol, args.server, args.port, args.key, args.courselab)
+            % (_tango_protocol, get_arg('server'), get_arg('port'), get_arg('key'), get_arg('courselab'))
         )
         print(
             "Sent request to %s:%d/open/%s/%s/"
-            % (args.server, args.port, args.key, args.courselab)
+            % (get_arg('server'), get_arg('port'), get_arg('key'), get_arg('courselab'))
         )
         print(response.text)
 
     except Exception as err:
         print(
             "Failed to send request to %s:%d/open/%s/%s/"
-            % (args.server, args.port, args.key, args.courselab)
+            % (get_arg('server'), get_arg('port'), get_arg('key'), get_arg('courselab'))
         )
         print(str(err))
         sys.exit(0)
@@ -210,28 +244,28 @@ def tango_upload():
         if res != 0:
             raise Exception("Invalid usage: [upload] " + upload_help)
 
-        f = open(args.filename)
-        dirs = args.filename.split("/")
+        dirs = get_arg('filename').split("/")
         filename = dirs[len(dirs) - 1]
         header = {"Filename": filename}
 
+        f = open(get_arg('filename'), 'rb')
         response = requests.post(
             "%s://%s:%d/upload/%s/%s/"
-            % (_tango_protocol, args.server, args.port, args.key, args.courselab),
+            % (_tango_protocol, get_arg('server'), get_arg('port'), get_arg('key'), get_arg('courselab')),
             data=f.read(),
             headers=header,
         )
         f.close()
         print(
             "Sent request to %s:%d/upload/%s/%s/ filename=%s"
-            % (args.server, args.port, args.key, args.courselab, args.filename)
+            % (get_arg('server'), get_arg('port'), get_arg('key'), get_arg('courselab'), get_arg('filename'))
         )
         print(response.text)
 
     except Exception as err:
         print(
             "Failed to send request to %s:%d/upload/%s/%s/ filename=%s"
-            % (args.server, args.port, args.key, args.courselab, args.filename)
+            % (get_arg('server'), get_arg('port'), get_arg('key'), get_arg('courselab'), get_arg('filename'))
         )
         print(str(err))
         sys.exit(0)
@@ -247,36 +281,37 @@ def tango_addJob():
         if res != 0:
             raise Exception("Invalid usage: [addJob] " + addJob_help)
 
-        requestObj["image"] = args.image
-        requestObj["files"] = args.infiles
-        requestObj["timeout"] = args.timeout
-        requestObj["max_kb"] = args.maxsize
-        requestObj["output_file"] = args.outputFile
-        requestObj["jobName"] = args.jobname
-
-        if args.notifyURL:
-            requestObj["notifyURL"] = args.notifyURL
-
-        requestObj["accessKeyId"] = args.accessKeyId
-        requestObj["accessKey"] = args.accessKey
-        requestObj["disable_network"] = args.disableNetwork
-        requestObj["instanceType"] = args.instanceType
+        requestObj = RequestObj(
+            image=get_arg('image'),
+            files=get_arg('infiles'),
+            timeout=get_arg('timeout'),
+            max_kb=get_arg('maxsize'),
+            output_file=get_arg('outputFile'),
+            jobName=get_arg('jobname'),
+            accessKeyId=get_arg('accessKeyId'),
+            accessKey=get_arg('accessKey'),
+            disable_network=get_arg('disableNetwork'),
+            instanceType=get_arg('instanceType'),
+            stopBefore=get_arg('stopBefore'),
+            notifyURL=get_arg('notifyURL'),
+            callback_url=get_arg('callbackURL'),
+        )
 
         response = requests.post(
             "%s://%s:%d/addJob/%s/%s/"
-            % (_tango_protocol, args.server, args.port, args.key, args.courselab),
-            data=json.dumps(requestObj),
+            % (_tango_protocol, get_arg('server'), get_arg('port'), get_arg('key'), get_arg('courselab')),
+            data=json.dumps(asdict(requestObj)),
         )
         print(
             "Sent request to %s:%d/addJob/%s/%s/ \t jobObj=%s"
-            % (args.server, args.port, args.key, args.courselab, json.dumps(requestObj))
+            % (get_arg('server'), get_arg('port'), get_arg('key'), get_arg('courselab'), json.dumps(asdict(requestObj)))
         )
         print(response.text)
 
     except Exception as err:
         print(
             "Failed to send request to %s:%d/addJob/%s/%s/ \t jobObj=%s"
-            % (args.server, args.port, args.key, args.courselab, json.dumps(requestObj))
+            % (get_arg('server'), get_arg('port'), get_arg('key'), get_arg('courselab'), json.dumps(asdict(requestObj)) if 'requestObj' in locals() else 'N/A')
         )
         print(str(err))
         sys.exit(0)
@@ -291,19 +326,19 @@ def tango_getPartialOutput():
             "%s://%s:%d/getPartialOutput/%s/%s/"
             % (
                 _tango_protocol,
-                args.server,
-                args.port,
-                args.key,
-                args.jobid,
+                get_arg('server'),
+                get_arg('port'),
+                get_arg('key'),
+                get_arg('jobid'),
             )
         )
         print(
             "Sent request to %s:%d/getPartialOutput/%s/%s/"
             % (
-                args.server,
-                args.port,
-                args.key,
-                args.jobid,
+                get_arg('server'),
+                get_arg('port'),
+                get_arg('key'),
+                get_arg('jobid'),
             )
         )
         print(response.text)
@@ -311,10 +346,10 @@ def tango_getPartialOutput():
         print(
             "Failed to send request to %s:%d/getPartialOutput/%s/%s/"
             % (
-                args.server,
-                args.port,
-                args.key,
-                args.jobid,
+                get_arg('server'),
+                get_arg('port'),
+                get_arg('key'),
+                get_arg('jobid'),
             )
         )
         print(str(err))
@@ -334,21 +369,21 @@ def tango_poll():
             "%s://%s:%d/poll/%s/%s/%s/"
             % (
                 _tango_protocol,
-                args.server,
-                args.port,
-                args.key,
-                args.courselab,
-                urllib.parse.quote(args.outputFile),
+                get_arg('server'),
+                get_arg('port'),
+                get_arg('key'),
+                get_arg('courselab'),
+                urllib.parse.quote(get_arg('outputFile')),
             )
         )
         print(
             "Sent request to %s:%d/poll/%s/%s/%s/"
             % (
-                args.server,
-                args.port,
-                args.key,
-                args.courselab,
-                urllib.parse.quote(args.outputFile),
+                get_arg('server'),
+                get_arg('port'),
+                get_arg('key'),
+                get_arg('courselab'),
+                urllib.parse.quote(get_arg('outputFile')),
             )
         )
         print(response.text)
@@ -357,11 +392,11 @@ def tango_poll():
         print(
             "Failed to send request to %s:%d/poll/%s/%s/%s/"
             % (
-                args.server,
-                args.port,
-                args.key,
-                args.courselab,
-                urllib.parse.quote(args.outputFile),
+                get_arg('server'),
+                get_arg('port'),
+                get_arg('key'),
+                get_arg('courselab'),
+                urllib.parse.quote(get_arg('outputFile')),
             )
         )
         print(str(err))
@@ -378,15 +413,15 @@ def tango_info():
             raise Exception("Invalid usage: [info] " + info_help)
 
         response = requests.get(
-            "%s://%s:%d/info/%s/" % (_tango_protocol, args.server, args.port, args.key)
+            "%s://%s:%d/info/%s/" % (_tango_protocol, get_arg('server'), get_arg('port'), get_arg('key'))
         )
-        print("Sent request to %s:%d/info/%s/" % (args.server, args.port, args.key))
+        print("Sent request to %s:%d/info/%s/" % (get_arg('server'), get_arg('port'), get_arg('key')))
         print(response.text)
 
     except Exception as err:
         print(
             "Failed to send request to %s:%d/info/%s/"
-            % (args.server, args.port, args.key)
+            % (get_arg('server'), get_arg('port'), get_arg('key'))
         )
         print(str(err))
         sys.exit(0)
@@ -403,18 +438,18 @@ def tango_jobs():
 
         response = requests.get(
             "%s://%s:%d/jobs/%s/%d/"
-            % (_tango_protocol, args.server, args.port, args.key, args.deadJobs)
+            % (_tango_protocol, get_arg('server'), get_arg('port'), get_arg('key'), get_arg('deadJobs'))
         )
         print(
             "Sent request to %s:%d/jobs/%s/%d/"
-            % (args.server, args.port, args.key, args.deadJobs)
+            % (get_arg('server'), get_arg('port'), get_arg('key'), get_arg('deadJobs'))
         )
         print(response.text)
 
     except Exception as err:
         print(
             "Failed to send request to %s:%d/jobs/%s/%d/"
-            % (args.server, args.port, args.key, args.deadJobs)
+            % (get_arg('server'), get_arg('port'), get_arg('key'), get_arg('deadJobs'))
         )
         print(str(err))
         sys.exit(0)
@@ -431,18 +466,18 @@ def tango_pool():
 
         response = requests.get(
             "%s://%s:%d/pool/%s/%s/"
-            % (_tango_protocol, args.server, args.port, args.key, args.image)
+            % (_tango_protocol, get_arg('server'), get_arg('port'), get_arg('key'), get_arg('image'))
         )
         print(
             "Sent request to %s:%d/pool/%s/%s/"
-            % (args.server, args.port, args.key, args.image)
+            % (get_arg('server'), get_arg('port'), get_arg('key'), get_arg('image'))
         )
         print(response.text)
 
     except Exception as err:
         print(
             "Failed to send request to %s:%d/pool/%s/%s/"
-            % (args.server, args.port, args.key, args.image)
+            % (get_arg('server'), get_arg('port'), get_arg('key'), get_arg('image'))
         )
         print(str(err))
         sys.exit(0)
@@ -458,23 +493,23 @@ def tango_prealloc():
         if res != 0:
             raise Exception("Invalid usage: [prealloc] " + prealloc_help)
 
-        vmObj["vmms"] = args.vmms
-        vmObj["cores"] = args.cores
-        vmObj["memory"] = args.memory
+        vmObj["vmms"] = get_arg('vmms')
+        vmObj["cores"] = get_arg('cores')
+        vmObj["memory"] = get_arg('memory')
 
         response = requests.post(
             "%s://%s:%d/prealloc/%s/%s/%s/"
-            % (_tango_protocol, args.server, args.port, args.key, args.image, args.num),
+            % (_tango_protocol, get_arg('server'), get_arg('port'), get_arg('key'), get_arg('image'), get_arg('num')),
             data=json.dumps(vmObj),
         )
         print(
             "Sent request to %s:%d/prealloc/%s/%s/%s/ \t vmObj=%s"
             % (
-                args.server,
-                args.port,
-                args.key,
-                args.image,
-                args.num,
+                get_arg('server'),
+                get_arg('port'),
+                get_arg('key'),
+                get_arg('image'),
+                get_arg('num'),
                 json.dumps(vmObj),
             )
         )
@@ -484,11 +519,11 @@ def tango_prealloc():
         print(
             "Failed to send request to %s:%d/prealloc/%s/%s/%s/ \t vmObj=%s"
             % (
-                args.server,
-                args.port,
-                args.key,
-                args.image,
-                args.num,
+                get_arg('server'),
+                get_arg('port'),
+                get_arg('key'),
+                get_arg('image'),
+                get_arg('num'),
                 json.dumps(vmObj),
             )
         )
@@ -514,21 +549,21 @@ def tango_build():
         if res != 0:
             raise Exception("Invalid usage: [build] " + build_help)
 
-        f = open(args.filename, "rb")
-        header = {"imageName": args.imageName}
+        f = open(get_arg('filename'), "rb")
+        header = {"imageName": get_arg('imageName')}
         response = requests.post(
             "%s://%s:%d/build/%s/"
-            % (_tango_protocol, args.server, args.port, args.key),
+            % (_tango_protocol, get_arg('server'), get_arg('port'), get_arg('key')),
             data=f.read(),
             headers=header,
         )
-        print("Sent request to %s:%d/build/%s/" % (args.server, args.port, args.key))
+        print("Sent request to %s:%d/build/%s/" % (get_arg('server'), get_arg('port'), get_arg('key')))
         print(response.text)
 
     except Exception as err:
         print(
             "Failed to send request to %s:%d/build/%s/"
-            % (args.server, args.port, args.key)
+            % (get_arg('server'), get_arg('port'), get_arg('key'))
         )
         print(str(err))
         sys.exit(0)
@@ -538,11 +573,11 @@ def tango_build():
 
 
 def tango_runJob():
-    if args.runJob is None:
+    if get_arg('runJob') is None:
         print("Invalid usage: [runJob]")
         sys.exit(0)
 
-    dir = args.runJob
+    dir = get_arg('runJob')
     infiles = [
         file for file in os.listdir(dir) if os.path.isfile(os.path.join(dir, file))
     ]
@@ -551,7 +586,7 @@ def tango_runJob():
 
     args.jobname += "-0"
     args.outputFile += "-0"
-    for i in range(1, args.numJobs + 1):
+    for i in range(1, get_arg('numJobs') + 1):
         print(
             "----------------------------------------- STARTING JOB "
             + str(i)
@@ -574,27 +609,27 @@ def tango_runJob():
 
 
 def router():
-    if args.open:
+    if get_arg('open'):
         tango_open()
-    elif args.upload:
+    elif get_arg('upload'):
         tango_upload()
-    elif args.addJob:
+    elif get_arg('addJob'):
         tango_addJob()
-    elif args.poll:
+    elif get_arg('poll'):
         tango_poll()
-    elif args.info:
+    elif get_arg('info'):
         tango_info()
-    elif args.jobs:
+    elif get_arg('jobs'):
         tango_jobs()
-    elif args.pool:
+    elif get_arg('pool'):
         tango_pool()
-    elif args.prealloc:
+    elif get_arg('prealloc'):
         tango_prealloc()
-    elif args.runJob:
+    elif get_arg('runJob'):
         tango_runJob()
-    elif args.getPartialOutput:
+    elif get_arg('getPartialOutput'):
         tango_getPartialOutput()
-    elif args.build:
+    elif get_arg('build'):
         tango_build()
 
 
@@ -603,32 +638,32 @@ def router():
 #
 args = parser.parse_args()
 if (
-    not args.open
-    and not args.upload
-    and not args.addJob
-    and not args.poll
-    and not args.info
-    and not args.jobs
-    and not args.pool
-    and not args.prealloc
-    and not args.runJob
-    and not args.getPartialOutput
-    and not args.build
+    not get_arg('open')
+    and not get_arg('upload')
+    and not get_arg('addJob')
+    and not get_arg('poll')
+    and not get_arg('info')
+    and not get_arg('jobs')
+    and not get_arg('pool')
+    and not get_arg('prealloc')
+    and not get_arg('runJob')
+    and not get_arg('getPartialOutput')
+    and not get_arg('build')
 ):
     parser.print_help()
     sys.exit(0)
 
-if args.ssl:
+if get_arg('ssl'):
     _tango_protocol = "https"
-    if args.port == 3000:
+    if get_arg('port') == 3000:
         args.port = 443
 
 
 try:
-    response = requests.get("%s://%s:%d/" % (_tango_protocol, args.server, args.port))
+    response = requests.get("%s://%s:%d/" % (_tango_protocol, get_arg('server'), get_arg('port')))
     response.raise_for_status()
 except BaseException:
-    print("Tango not reachable on %s:%d!\n" % (args.server, args.port))
+    print("Tango not reachable on %s:%d!\n" % (get_arg('server'), get_arg('port')))
     sys.exit(0)
 
 router()
diff --git a/jobManager.py b/jobManager.py
index c31b9bc4..752c670a 100644
--- a/jobManager.py
+++ b/jobManager.py
@@ -11,9 +11,9 @@
 #
 
 import copy
-import time
 import logging
 import threading
+import time
 import traceback
 from datetime import datetime
 
@@ -21,8 +21,6 @@
 from config import Config
 from tangoObjects import TangoQueue
 from worker import Worker
-from preallocator import Preallocator
-from jobQueue import JobQueue
 
 
 class JobManager(object):
@@ -74,10 +72,11 @@ def __manage(self):
             try:
                 # if the job is a ec2 vmms job
                 # spin up an ec2 instance for that job
-                if job.vm.ec2_vmms:
+                if Config.VMMS_NAME == "ec2SSH":
                     from vmms.ec2SSH import Ec2SSH
 
                     vmms = Ec2SSH(job.accessKeyId, job.accessKey)
+
                     newVM = copy.deepcopy(job.vm)
                     newVM.id = self._getNextID()
                     try:
@@ -86,7 +85,9 @@ def __manage(self):
                         self.log.error("ERROR initialization VM: %s", e)
                         self.log.error(traceback.format_exc())
                     if preVM is None:
-                        raise Exception("EC2 SSH VM initialization failed: see log")
+                        raise Exception(
+                            "EC2 SSH VM initialization failed: see log"
+                        )
                 else:
                     # Try to find a vm on the free list and allocate it to
                     # the worker if successful.
@@ -113,17 +114,24 @@ def __manage(self):
                 )
                 # Mark the job assigned
                 self.jobQueue.assignJob(job.id, preVM)
-                Worker(job, vmms, self.jobQueue, self.preallocator, preVM).start()
+                Worker(
+                    job, vmms, self.jobQueue, self.preallocator, preVM
+                ).start()
 
             except Exception as err:
-                self.log.error("job failed during creation %d %s" % (job.id, str(err)))
-                self.jobQueue.makeDead(job.id, str(err))
+                if job is None:
+                    self.log.info("job_manager: job is None")
+                else:
+                    self.log.error(
+                        "job failed during creation %d %s" % (job.id, str(err))
+                    )
+                    self.jobQueue.makeDead(job.id, str(err))
 
 
 if __name__ == "__main__":
 
     if not Config.USE_REDIS:
-        print(
+        tango.log.error(
             "You need to have Redis running to be able to initiate stand-alone\
          JobManager"
         )
@@ -133,7 +141,14 @@ def __manage(self):
         tango.resetTango(tango.preallocator.vmms)
         for key in tango.preallocator.machines.keys():
             tango.preallocator.machines.set(key, [[], TangoQueue(key)])
+
+            # The above call sets the total pool empty.  But the free pool which
+            # is a queue in redis, may not be empty.  When the job manager restarts,
+            # resetting the free queue using the key doesn't change its content.
+            # Therefore we empty the queue, thus the free pool, to keep it consistent
+            # with the total pool.
+            tango.preallocator.machines.get(key)[1].make_empty()
         jobs = JobManager(tango.jobQueue)
 
-        print("Starting the stand-alone Tango JobManager")
+        tango.log.info("Starting the stand-alone Tango JobManager")
         jobs.run()
diff --git a/preallocator.py b/preallocator.py
index 9d7670e9..93e9c822 100644
--- a/preallocator.py
+++ b/preallocator.py
@@ -47,6 +47,7 @@ def update(self, vm, num):
         self.lock.acquire()
         if vm.name not in self.machines:
             self.machines.set(vm.name, [[], TangoQueue(vm.name)])
+            self.machines.get(vm.name)[1].make_empty()
             self.log.debug("Creating empty pool of %s instances" % (vm.name))
         self.lock.release()
 
diff --git a/requirements.txt b/requirements.txt
index 0591f3e7..548d9625 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -9,3 +9,4 @@ urllib3==1.26.19
 docker==5.0.3
 backoff==2.2.1
 pytz
+pyyaml
diff --git a/restful_tango/tangoREST.py b/restful_tango/tangoREST.py
index 39774111..c6a13686 100644
--- a/restful_tango/tangoREST.py
+++ b/restful_tango/tangoREST.py
@@ -164,9 +164,11 @@ def convertJobObj(self, dirName, jobObj):
             )
             input.append(handinfile)
 
-        ec2_vmms = False
-        if "ec2Vmms" in jobObj:
-            ec2_vmms = True
+        ec2_vmms = Config.VMMS_NAME == "ec2SSH"
+
+        stopBefore = ""
+        if "stopBefore" in jobObj:
+            stopBefore = jobObj["stopBefore"]
 
         instance_type = None
         if "instanceType" in jobObj and len(jobObj["instanceType"]) > 0:
@@ -198,6 +200,7 @@ def convertJobObj(self, dirName, jobObj):
             accessKey=accessKey,
             accessKeyId=accessKeyId,
             disableNetwork=disableNetwork,
+            stopBefore=stopBefore
         )
 
         self.log.debug("inputFiles: %s" % [file.localFile for file in input])
diff --git a/tangoObjects.py b/tangoObjects.py
index 2dc03dbe..899c3181 100644
--- a/tangoObjects.py
+++ b/tangoObjects.py
@@ -100,6 +100,7 @@ def __init__(
         accessKeyId=None,
         accessKey=None,
         disableNetwork=None,
+        stopBefore="",
     ):
         self.assigned = False
         self.retries = 0
@@ -120,6 +121,7 @@ def __init__(
         self.accessKeyId = accessKeyId
         self.accessKey = accessKey
         self.disableNetwork = disableNetwork
+        self.stopBefore = "stopBefore"
 
     def __repr__(self):
         self.syncRemote()
@@ -319,6 +321,9 @@ def remove(self, item):
     def _clean(self):
         self.__db.delete(self.key)
 
+    def make_empty(self):
+        self.__db.delete(self.key)
+
 
 # This is an abstract class that decides on
 # if we should initiate a TangoRemoteDictionary or TangoNativeDictionary
diff --git a/tests/sample_test/expected_output.txt b/tests/sample_test/expected_output.txt
new file mode 100644
index 00000000..70c379b6
--- /dev/null
+++ b/tests/sample_test/expected_output.txt
@@ -0,0 +1 @@
+Hello world
\ No newline at end of file
diff --git a/tests/sample_test/input/autograde-Makefile b/tests/sample_test/input/autograde-Makefile
new file mode 100644
index 00000000..10870823
--- /dev/null
+++ b/tests/sample_test/input/autograde-Makefile
@@ -0,0 +1,2 @@
+autograde:
+	bash hello.sh
diff --git a/tests/sample_test/input/hello.sh b/tests/sample_test/input/hello.sh
new file mode 100755
index 00000000..46c0d0e9
--- /dev/null
+++ b/tests/sample_test/input/hello.sh
@@ -0,0 +1,3 @@
+#!/bin/bash
+
+echo "Hello world"
diff --git a/tests/sample_test/sample_test.yaml b/tests/sample_test/sample_test.yaml
new file mode 100644
index 00000000..43dd5030
--- /dev/null
+++ b/tests/sample_test/sample_test.yaml
@@ -0,0 +1,11 @@
+num_submissions: 5
+submission_delay: 0.1
+autograder_image: ec2_213_llvm_14_s25
+output_file: log.txt
+tango_port: 3001
+cli_path: /home/snarita/Autolab/Tango/clients/tango-cli.py
+instance_type: t2.micro
+timeout: 180
+ec2: True
+expected_output: expected_output.txt
+stop_before:
diff --git a/tests/stressTest.py b/tests/stressTest.py
new file mode 100644
index 00000000..6494a8c4
--- /dev/null
+++ b/tests/stressTest.py
@@ -0,0 +1,161 @@
+import argparse
+import subprocess
+import time
+import os
+import sys
+
+import tornado.web
+
+import yaml
+
+test_dir = ""
+sub_num = 0
+finished_tests = dict()
+start_time = time.time()
+expected_output = ""
+
+def printProgressBar (iteration, total, prefix = '', suffix = '', decimals = 1, length = 100, fill = '█', printEnd = "\r"):
+    """
+    Call in a loop to create terminal progress bar
+    @params:
+        iteration   - Required  : current iteration (Int)
+        total       - Required  : total iterations (Int)
+        prefix      - Optional  : prefix string (Str)
+        suffix      - Optional  : suffix string (Str)
+        decimals    - Optional  : positive number of decimals in percent complete (Int)
+        length      - Optional  : character length of bar (Int)
+        fill        - Optional  : bar fill character (Str)
+        printEnd    - Optional  : end character (e.g. "\r", "\r\n") (Str)
+    """
+    percent = ("{0:." + str(decimals) + "f}").format(100 * (iteration / float(total)))
+    filledLength = int(length * iteration // total)
+    bar = fill * filledLength + '-' * (length - filledLength)
+    print(f'\r{prefix} |{bar}| {percent}% {suffix}', end = printEnd)
+    # Print New Line on Complete
+    if iteration == total: 
+        print()
+
+def run_stress_test(num_submissions, submission_delay, autograder_image, output_file, tango_port, cli_path, 
+                    job_name, job_path, instance_type, timeout, ec2):
+    printProgressBar(0, num_submissions, prefix = 'Jobs Added:', suffix = 'Complete', length = 50)
+    with open(output_file, 'a') as f:
+        f.write(f"Stress testing with {num_submissions} submissions\n")
+        
+        for i in range(1, num_submissions + 1):
+            command = [
+                'python3', cli_path,
+                '-P', str(tango_port),
+                '-k', 'test',
+                '-l', job_name,
+                '--runJob', job_path,
+                '--image', autograder_image,
+                '--instanceType', instance_type,
+                '--timeout', str(timeout),
+                '--callbackURL', ("http://localhost:8888/autograde_done?id=%d" % (i))
+            ]
+            if ec2:
+                command += ['--ec2']
+            subprocess.run(command, stdout=f, stderr=f)
+            f.write(f"Submission {i} completed\n")
+            printProgressBar(i, num_submissions, prefix = 'Jobs Added:', suffix = 'Complete', length = 50)
+            if submission_delay > 0:
+                time.sleep(submission_delay)
+        print()
+
+class AutogradeDoneHandler(tornado.web.RequestHandler):
+    def post(self):
+        global finished_tests
+        global test_dir
+        global sub_num
+        global start_time
+        id = self.get_query_argument("id")
+        fileBody = self.request.files["file"][0]["body"].decode()
+        scoreJson = fileBody.split("\n")[-2]
+        with open(os.path.join(test_dir, "output", "output%s.txt" % id), 'w') as f:
+            f.write(fileBody)
+        finished_tests[str(id)] = scoreJson
+        printProgressBar(len(finished_tests), sub_num, prefix = 'Tests Done:', suffix = 'Complete', length = 50)
+        self.write("ok")
+        self.flush()
+
+    def on_finish(self):
+        global finished_tests, sub_num, shutdown_event
+        if len(finished_tests) == sub_num:
+            print("\nAll tests completed. Generating summary...")
+            create_summary()
+            print("Test Summary in summary.txt")
+            print("\nShutting down server...")
+            tornado.ioloop.IOLoop.current().stop()
+
+def create_summary():
+    success = []
+    failed = []
+    for i in range(1, sub_num + 1):
+        if expected_output == finished_tests[str(i)]:
+            success.append(i)
+        else:
+            failed.append(i)
+    with open(os.path.join(test_dir, "summary.txt"), 'w') as f:
+        f.write("Total Time: %d seconds\n" % (time.time() - start_time))
+        f.write("Total Succeeded: %d / %d\n" % (len(success), sub_num))
+        f.write("Total Failed: %d / %d\n" % (len(failed), sub_num))
+        f.write("\n===========================================================\n")
+        f.write("The expected value is:\n")
+        f.write(expected_output)
+        f.write("\n\n===========================================================\n")
+        f.write("Failed Cases:\n")
+        for i in range(0, len(failed)):
+            f.write("Test Case #%d: %s\n" % (failed[i], finished_tests[str(failed[i])]))
+
+def make_app():
+    return tornado.web.Application([
+        (r"/autograde_done", AutogradeDoneHandler),
+    ])
+
+def notifyServer():
+    global shutdown_event
+    app = make_app()
+    app.listen(8888)
+    printProgressBar(0, sub_num, prefix = 'Tests Done:', suffix = 'Complete', length = 50)
+    tornado.ioloop.IOLoop.current().start()
+
+if __name__ == "__main__":
+    parser = argparse.ArgumentParser(description="Stress test script for Tango")
+    parser.add_argument('--test_dir', type=str, required=True, help="Directory to run the test in")
+
+    args = parser.parse_args()
+
+    dirname = os.path.basename(args.test_dir)
+
+    test_dir = args.test_dir
+
+    with open(os.path.join(args.test_dir, dirname + '.yaml'), 'r') as f:
+        data = yaml.load(f, Loader=yaml.SafeLoader)
+    
+    with open(os.path.join(args.test_dir, data["expected_output"]), 'r') as f:
+        expected_output = f.read()
+
+    sub_num = data["num_submissions"]
+    finished_tests = dict()
+    start_time = time.time()
+
+    subprocess.run("rm -rf %s/output" % args.test_dir, shell=True)
+    subprocess.run("mkdir %s/output" % args.test_dir, shell=True)
+
+    print()
+
+    run_stress_test(
+        data["num_submissions"],
+        data["submission_delay"],
+        data["autograder_image"],
+        os.path.join(args.test_dir, data["output_file"]),
+        data["tango_port"],
+        data["cli_path"],
+        dirname,
+        os.path.join(args.test_dir, 'input'),
+        data["instance_type"],
+        data["timeout"],
+        data["ec2"]
+    )
+
+    notifyServer()
\ No newline at end of file
diff --git a/vmms/ec2SSH.py b/vmms/ec2SSH.py
index c6616afc..e3b7607c 100644
--- a/vmms/ec2SSH.py
+++ b/vmms/ec2SSH.py
@@ -8,21 +8,19 @@
 #   Ec2Exception - EC2 raises this if it encounters any problem
 #   ec2CallError - raised by ec2Call() function
 #
-# TODO: this currently probably does not work on Python 3 yet
 
-import subprocess
+import logging
 import os
 import re
-import time
-import logging
+import subprocess
 import threading
-import config
+import time
+
 import backoff
 import boto3
 from botocore.exceptions import ClientError
 
-import pytz
-
+import config
 from tangoObjects import TangoMachine
 
 # suppress most boto logging
@@ -222,13 +220,6 @@ def __init__(self, accessKeyId=None, accessKey=None):
         taggedAMIs = [self.img2ami[key].id for key in self.img2ami]
         ignoredAMIs = list(set(imageAMIs) - set(taggedAMIs))
 
-        self.log.info("imageAMIs")
-        self.log.info(imageAMIs)
-        self.log.info("taggedAMIs")
-        self.log.info(taggedAMIs)
-        self.log.info("ignoredAMIs")
-        self.log.info(ignoredAMIs)
-
         if len(ignoredAMIs) > 0:
             self.log.info(
                 "Ignored images %s for lack of or ill-formed name tag"
@@ -381,23 +372,34 @@ def initializeVM(self, vm):
             start_time = time.time()
             while True:
 
-                filters = [{"Name": "instance-state-name", "Values": ["running"]}]
+                filters = [
+                    {"Name": "instance-state-name", "Values": ["running"]}
+                ]
                 instances = self.boto3resource.instances.filter(Filters=filters)
                 instanceRunning = False
 
                 # reload the state of the new instance
                 try_load_instance(newInstance)
                 for inst in instances.filter(InstanceIds=[newInstance.id]):
-                    self.log.debug("VM %s %s: is running" % (vm.name, newInstance.id))
+                    self.log.debug(
+                        "VM %s %s: is running" % (vm.name, newInstance.id)
+                    )
                     instanceRunning = True
 
                 if instanceRunning:
                     break
 
-                if time.time() - start_time > config.Config.INITIALIZEVM_TIMEOUT:
+                if (
+                    time.time() - start_time
+                    > config.Config.INITIALIZEVM_TIMEOUT
+                ):
                     raise ValueError(
                         "VM %s %s: timeout (%d seconds) before reaching 'running' state"
-                        % (vm.name, newInstance.id, config.Config.TIMER_POLL_INTERVAL)
+                        % (
+                            vm.name,
+                            newInstance.id,
+                            config.Config.TIMER_POLL_INTERVAL,
+                        )
                     )
 
                 self.log.debug(
@@ -408,7 +410,8 @@ def initializeVM(self, vm):
 
             # Assign name to EC2 instance
             self.boto3resource.create_tags(
-                Resources=[newInstance.id], Tags=[{"Key": "Name", "Value": vm.name}]
+                Resources=[newInstance.id],
+                Tags=[{"Key": "Name", "Value": vm.name}],
             )
 
             self.log.info(
@@ -510,18 +513,28 @@ def waitVM(self, vm, max_secs):
             # Sleep a bit before trying again
             time.sleep(config.Config.TIMER_POLL_INTERVAL)
 
-    def copyIn(self, vm, inputFiles):
-        """copyIn - Copy input files to VM"""
-        self.log.info("copyIn %s - writing files" % self.instanceName(vm.id, vm.name))
+    def copyIn(self, vm, inputFiles, job_id=None):
+        """copyIn - Copy input files to VM
+        Args:
+        - vm is a TangoMachine object
+        - inputFiles is a list of objects with attributes localFile and destFile. 
+            localFile is the file on the host, destFile is the file on the VM.
+        - job_id is the job id of the job being run on the VM. 
+            It is used for logging purposes only.
+        """
+        self.log.info(
+            "copyIn %s - writing files" % self.instanceName(vm.id, vm.name)
+        )
 
         domain_name = self.domainName(vm)
 
+        # Creates directory and add permissions
         result = subprocess.run(
             ["ssh"]
             + self.ssh_flags
             + [
                 "%s@%s" % (self.ec2User, domain_name),
-                "(mkdir autolab)",
+                "(mkdir -p autolab && chmod 775 autolab)",
             ],
             stdout=subprocess.PIPE,
             stderr=subprocess.PIPE,
@@ -530,11 +543,22 @@ def copyIn(self, vm, inputFiles):
 
         # Print the output and error
         for line in result.stdout:
-            self.log.info("%s" % line)
-        self.log.info("Standard Error: %s" % result.stderr)
-        self.log.info("Return Code: %s" % result.returncode)
+            self.log.info("%s for job %s" % (line, job_id))
+        self.log.info("Return Code: %s, job: %s" % (result.returncode, job_id))
+        if result.stderr != 0:
+            self.log.info(
+                "Standard Error: %s, job: %s" % (result.stderr, job_id)
+            )
+
+        # Validate inputFiles structure
+        if not inputFiles or not all(
+            hasattr(file, "localFile") and hasattr(file, "destFile")
+            for file in inputFiles
+        ):
+            self.log.info(
+                "Error: Invalid inputFiles Structure, job: %s" % job_id
+            )
 
-        # Copy the input files to the input directory
         for file in inputFiles:
             self.log.info("%s - %s" % (file.localFile, file.destFile))
             ret = timeout_with_retries(
@@ -542,11 +566,13 @@ def copyIn(self, vm, inputFiles):
                 + self.ssh_flags
                 + [
                     file.localFile,
-                    "%s@%s:~/autolab/%s" % (self.ec2User, domain_name, file.destFile),
+                    "%s@%s:~/autolab/%s"
+                    % (self.ec2User, domain_name, file.destFile),
                 ],
                 config.Config.COPYIN_TIMEOUT,
             )
             if ret != 0:
+                self.log.info("Copy-in Error: SCP failure, job: %s" % job_id)
                 return ret
 
         return 0
@@ -574,7 +600,9 @@ def runJob(self, vm, runTimeout, maxOutputFileSize, disableNetwork):
         # no logging for now
 
         ret = timeout(
-            ["ssh"] + self.ssh_flags + ["%s@%s" % (self.ec2User, domain_name), runcmd],
+            ["ssh"]
+            + self.ssh_flags
+            + ["%s@%s" % (self.ec2User, domain_name), runcmd],
             runTimeout * 2,
         )
 
@@ -586,7 +614,9 @@ def copyOut(self, vm, destFile):
         outputFile on the Tango host.
         """
         self.log.info(
-            "copyOut %s - writing to %s", self.instanceName(vm.id, vm.name), destFile
+            "copyOut %s - writing to %s",
+            self.instanceName(vm.id, vm.name),
+            destFile,
         )
         domain_name = self.domainName(vm)
 
@@ -631,7 +661,10 @@ def copyOut(self, vm, destFile):
         return timeout(
             ["scp"]
             + self.ssh_flags
-            + ["%s@%s:output" % (config.Config.EC2_USER_NAME, domain_name), destFile],
+            + [
+                "%s@%s:output" % (config.Config.EC2_USER_NAME, domain_name),
+                destFile,
+            ],
             config.Config.COPYOUT_TIMEOUT,
         )
 
@@ -647,7 +680,9 @@ def destroyVM(self, vm):
                 InstanceIds=[vm.instance_id]
             )
             if not instances:
-                self.log.debug("no instances found with instance id %s", vm.instance_id)
+                self.log.debug(
+                    "no instances found with instance id %s", vm.instance_id
+                )
             # Keep the vm and mark with meaningful tags for debugging
             if (
                 hasattr(config.Config, "KEEP_VM_AFTER_FAILURE")
@@ -674,7 +709,9 @@ def destroyVM(self, vm):
             if not self.useDefaultKeyPair:
                 self.deleteKeyPair()
         except Exception as e:
-            self.log.error("destroyVM failed: %s for vm %s" % (e, vm.instance_id))
+            self.log.error(
+                "destroyVM failed: %s for vm %s" % (e, vm.instance_id)
+            )
 
         Ec2SSH.release_vm_semaphore()
 
@@ -688,7 +725,10 @@ def getVMs(self):
         try:
             vms = list()
             filters = [
-                {"Name": "instance-state-name", "Values": ["running", "pending"]}
+                {
+                    "Name": "instance-state-name",
+                    "Values": ["running", "pending"],
+                }
             ]
             # gets all running instances
             instances = self.boto3resource.instances.filter(Filters=filters)
@@ -705,8 +745,13 @@ def getVMs(self):
                     instance.tags, "Name"
                 )  # inst name PREFIX-serial-IMAGE
                 # Name tag is the standard form of prefix-serial-image
-                if not (instName and re.match("%s-" % config.Config.PREFIX, instName)):
-                    self.log.debug("getVMs: Instance id %s skipped" % vm.instance_id)
+                if not (
+                    instName
+                    and re.match("%s-" % config.Config.PREFIX, instName)
+                ):
+                    self.log.debug(
+                        "getVMs: Instance id %s skipped" % vm.instance_id
+                    )
                     continue  # instance without name tag or proper prefix
 
                 vm.name = instName
@@ -720,7 +765,8 @@ def getVMs(self):
 
                 vms.append(vm)
                 self.log.debug(
-                    "getVMs: Instance id %s, name %s" % (vm.instance_id, vm.name)
+                    "getVMs: Instance id %s, name %s"
+                    % (vm.instance_id, vm.name)
                 )
         except Exception as e:
             self.log.debug("getVMs Failed: %s" % e)
@@ -762,11 +808,13 @@ def getPartialOutput(self, vm):
         )
 
         sshcmd = (
-            ["ssh"] + self.ssh_flags + ["%s@%s" % (self.ec2User, domain_name), runcmd]
+            ["ssh"]
+            + self.ssh_flags
+            + ["%s@%s" % (self.ec2User, domain_name), runcmd]
         )
 
-        output = subprocess.check_output(sshcmd, stderr=subprocess.STDOUT).decode(
-            "utf-8"
-        )
+        output = subprocess.check_output(
+            sshcmd, stderr=subprocess.STDOUT
+        ).decode("utf-8")
 
         return output
diff --git a/worker.py b/worker.py
index 1d197337..b49489f0 100644
--- a/worker.py
+++ b/worker.py
@@ -49,7 +49,7 @@ def detachVM(self, return_vm=False, replace_vm=False):
         this function before returning.
         """
         # job-owned instance, simply destroy after job is completed
-        if self.job.vm.ec2_vmms:
+        if Config.VMMS_NAME == "ec2SSH":
             self.vmms.safeDestroyVM(self.job.vm)
         elif return_vm:
             self.preallocator.freeVM(self.job.vm)
@@ -254,6 +254,12 @@ def run(self):
                 )
             )
             self.log.debug("Waiting for VM")
+            if self.job.stopBefore == "waitvm":
+                msg = "Execution stopped before %s" % self.job.stopBefore
+                returnVM = True
+                self.job.vm.keep_for_debugging = True
+                self.afterJobExecution(hdrfile, msg, returnVM)
+                return
             ret["waitvm"] = self.vmms.waitVM(vm, Config.WAITVM_TIMEOUT)
 
             self.log.debug("Waited for VM")
@@ -287,8 +293,17 @@ def run(self):
                 )
             )
 
+            if (self.job.stopBefore == "copyin"):
+                msg = "Execution stopped before %s" % self.job.stopBefore
+                returnVM = True
+                self.job.vm.keep_for_debugging = True
+                self.afterJobExecution(hdrfile, msg, returnVM)
+                return
             # Copy input files to VM
-            ret["copyin"] = self.vmms.copyIn(vm, self.job.input)
+            self.log.debug(f"Before copyIn: ret[copyin] = {ret['copyin']}, job_id: {str(self.job.id)}")
+            ret["copyin"] = self.vmms.copyIn(vm, self.job.input, self.job.id)
+            self.log.debug(f"After copyIn: ret[copyin] = {ret['copyin']}, job_id: {str(self.job.id)}")
+
             if ret["copyin"] != 0:
                 Config.copyin_errors += 1
                 msg = "Error: Copy in to VM failed (status=%d)" % (ret["copyin"])
@@ -306,6 +321,12 @@ def run(self):
                 % (datetime.now().ctime(), self.job.name, self.job.id, ret["copyin"])
             )
 
+            if (self.job.stopBefore == "runjob"):
+                msg = "Execution stopped before %s" % self.job.stopBefore
+                returnVM = True
+                self.job.vm.keep_for_debugging = True
+                self.afterJobExecution(hdrfile, msg, returnVM)
+                return
             # Run the job on the virtual machine
             ret["runjob"] = self.vmms.runJob(
                 vm,
@@ -326,6 +347,12 @@ def run(self):
                 % (datetime.now().ctime(), self.job.name, self.job.id, ret["runjob"])
             )
 
+            if (self.job.stopBefore == "copyout"):
+                msg = "Execution stopped before %s" % self.job.stopBefore
+                returnVM = True
+                self.job.vm.keep_for_debugging = True
+                self.afterJobExecution(hdrfile, msg, returnVM)
+                return
             # Copy the output back.
             ret["copyout"] = self.vmms.copyOut(vm, self.job.outputFile)
             if ret["copyout"] != 0: