feat: document live migration from TimescaleDB to Timescale (#2897)

* docs: live migration from TimescaleDB to Timescale
* docs: update PG to TS live migration doc

_partials/_migrate_live_migration_step2.md

@@ -0,0 +1,48 @@
+import SetupSourceTarget from "versionContent/_partials/_migrate_set_up_source_and_target.mdx";
+
+<SetupSourceTarget />
+
+It's important to ensure that the `old_snapshot_threshold` value is set to the
+default value of `-1` in your source database. This prevents PostgreSQL from
+treating the data in a snapshot as outdated. If this value is set other than
+`-1`, it might affect the existing data migration step.
+
+To check the current value of `old_snapshot_threshold`, run the command:
+
+```sh
+psql -X -d $SOURCE -c 'show old_snapshot_threshold'
+```
+
+If the query returns something other than `-1`, you must change it.
+
+If you have a superuser on a self-hosted database, run the following command:
+
+```sh
+psql -X -d $SOURCE -c 'alter system set old_snapshot_threshold=-1'
+```
+
+Otherwise, if you are using a managed service, use your cloud provider's
+configuration mechanism to set `old_snapshot_threshold` to `-1`.
+
+Next, you should set `wal_level` to `logical` so that the write-ahead log (WAL)
+records information that is needed for logical decoding.
+
+To check the current value of  `wal_level`, run the command:
+
+```sh
+psql -X -d $SOURCE -c 'show wal_level'
+```
+
+If the query returns something other than `logical`, you must change it.
+
+If you have a superuser on a self-hosted database, run the following command:
+
+```sh
+psql -X -d $SOURCE -c 'alter system set wal_level=logical'
+```
+
+Otherwise, if you are using a managed service, use your cloud provider's
+configuration mechanism to set `wal_level` to `logical`.
+
+Restart your database for the changes to take effect, and verify that the
+settings are reflected in your database.

migrate/live-migration/index.md

@@ -10,10 +10,9 @@ import SourceTargetNote from "versionContent/_partials/_migrate_source_target_no
 # Live migration
 
 Live migration is a migration strategy to move a large amount of data
-(100 GB-10 TB+) with low downtime (on the order of minutes of
-downtime). It is significantly more complicated to execute than a migration
-with downtime using [pg_dump/restore][pg-dump-and-restore], but supports more
-use-cases and has less requirements than the [dual-write and backfill] method.
+(100 GB-10 TB+) with low downtime (on the order of few minutes). It requires
+more steps to execute than a migration with downtime using [pg_dump/restore][pg-dump-and-restore],
+but supports more use-cases and has less requirements than the [dual-write and backfill] method.
 
 <SourceTargetNote />
 
@@ -27,20 +26,27 @@ Roughly, it consists of four steps:
 3. Copy data from source to target while capturing changes.
 4. Apply captured changes from source to target.
 
-Currently live migration only supports migrating from PostgreSQL, but we are
-actively working on supporting TimescaleDB.
-
 Live migration works well when:
 - Large, busy tables have primary keys, or don't have many `UPDATE` or
   `DELETE` statements.
-- The insert workload does not exceed 20'000 rows per second, and
+- The insert workload does not exceed 20,000 rows per second, and
   inserts are batched. If your application exceeds this, you should use
   the [dual-write and backfill] migration method.
 
-For more information, consult the step-by-step migration guide:
+For more information, refer to the step-by-step migration guide:
 
 - [Live migration from PostgreSQL][from-postgres]
+- [Live migration from TimescaleDB][from-timescaledb]
+
+If you want to manually migrate data from PostgreSQL, refer to
+[Live migration from PostgreSQL manually][live-migration-manual].
+
+If you are migrating from AWS RDS to Timescale, you can refer to [this][live-migration-playbook] playbook
+for a detailed migration guide.
 
 [from-postgres]: /migrate/:currentVersion:/live-migration/live-migration-from-postgres/
+[from-timescaledb]: /migrate/:currentVersion:/live-migration/live-migration-from-timescaledb/
+[live-migration-manual]: /migrate/:currentVersion:/playbooks/live-migration-from-timescaledb-manually/
 [pg-dump-and-restore]: /migrate/:currentVersion:/pg-dump-and-restore/
-[dual-write and backfill]: /migrate/:currentVersion:/dual-write-and-backfill/
+[dual-write and backfill]: /migrate/:currentVersion:/dual-write-and-backfill/
+[live-migration-playbook]: /migrate/:currentVersion:/playbooks/rds-timescale-live-migration/