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bsanchez-the-roach merged 3 commits into from
May 28, 2026
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MOLT May docs work #23402

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6b9c467
initial commit
bsanchez-the-roach May 27, 2026
1e18b3c
fixed skipped_unmigratable_tables format
bsanchez-the-roach May 28, 2026
ccfb20d
Merge branch 'main' into DOC-17277
bsanchez-the-roach May 28, 2026
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22 changes: 11 additions & 11 deletions src/current/_includes/molt/delta-all-sources.md
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Expand Up @@ -374,15 +374,15 @@ MOLT Fetch captures a consistent point-in-time checkpoint at the start of the da
You should see periodic primary keepalive messages:

~~~
DEBUG [Aug 25 14:38:10] primary keepalive received ReplyRequested=false ServerTime="2025-08-25 14:38:09.556773 -0500 CDT" ServerWALEnd=0/49913A58
DEBUG [Aug 25 14:38:15] primary keepalive received ReplyRequested=false ServerTime="2025-08-25 14:38:14.556836 -0500 CDT" ServerWALEnd=0/49913E60
DEBUG [2025-08-25T14:38:10-05:00] primary keepalive received ReplyRequested=false ServerTime="2025-08-25 14:38:09.556773 -0500 CDT" ServerWALEnd=0/49913A58
DEBUG [2025-08-25T14:38:15-05:00] primary keepalive received ReplyRequested=false ServerTime="2025-08-25 14:38:14.556836 -0500 CDT" ServerWALEnd=0/49913E60
~~~

When rows are successfully replicated, you should see debug output like the following:

~~~
DEBUG [Aug 25 14:40:02] upserted rows conflicts=0 duration=7.855333ms proposed=1 target="\"molt\".\"public\".\"tbl1\"" upserted=1
DEBUG [Aug 25 14:40:02] progressed to LSN: 0/49915DD0
DEBUG [2025-08-25T14:40:02-05:00] upserted rows conflicts=0 duration=7.855333ms proposed=1 target="\"molt\".\"public\".\"tbl1\"" upserted=1
DEBUG [2025-08-25T14:40:02-05:00] progressed to LSN: 0/49915DD0
~~~
</section>

Expand All @@ -392,30 +392,30 @@ MOLT Fetch captures a consistent point-in-time checkpoint at the start of the da
~~~
[2025/08/25 15:29:09] [info] binlogsyncer.go:463 begin to sync binlog from GTID set 77263736-7899-11f0-81a5-0242ac120002:1-38
[2025/08/25 15:29:09] [info] binlogsyncer.go:409 Connected to mysql 8.0.43 server
INFO [Aug 25 15:29:09] connected to MySQL version 8.0.43
INFO [2025-08-25T15:29:09-05:00] connected to MySQL version 8.0.43
~~~

When rows are successfully replicated, you should see debug output like the following:

~~~
DEBUG [Aug 25 15:29:38] upserted rows conflicts=0 duration=1.801ms proposed=1 target="\"molt\".\"public\".\"tbl1\"" upserted=1
DEBUG [Aug 25 15:29:38] progressed to consistent point: 77263736-7899-11f0-81a5-0242ac120002:1-39
DEBUG [2025-08-25T15:29:38-05:00] upserted rows conflicts=0 duration=1.801ms proposed=1 target="\"molt\".\"public\".\"tbl1\"" upserted=1
DEBUG [2025-08-25T15:29:38-05:00] progressed to consistent point: 77263736-7899-11f0-81a5-0242ac120002:1-39
~~~
</section>

<section class="filter-content" markdown="1" data-scope="oracle">
When transactions are read from the Oracle source, you should see registered transaction IDs (XIDs):

~~~
DEBUG [Jul 3 15:55:12] registered xid 0f001f0040060000
DEBUG [Jul 3 15:55:12] registered xid 0b001f00bb090000
DEBUG [2025-07-03T15:55:12-05:00] registered xid 0f001f0040060000
DEBUG [2025-07-03T15:55:12-05:00] registered xid 0b001f00bb090000
~~~

When rows are successfully replicated, you should see debug output like the following:

~~~
DEBUG [Jul 3 15:55:12] upserted rows conflicts=0 duration=2.620009ms proposed=13 target="\"molt_movies\".\"USERS\".\"CUSTOMER_CONTACT\"" upserted=13
DEBUG [Jul 3 15:55:12] upserted rows conflicts=0 duration=2.212807ms proposed=16 target="\"molt_movies\".\"USERS\".\"CUSTOMER_DEVICE\"" upserted=16
DEBUG [2025-07-03T15:55:12-05:00] upserted rows conflicts=0 duration=2.620009ms proposed=13 target="\"molt_movies\".\"USERS\".\"CUSTOMER_CONTACT\"" upserted=13
DEBUG [2025-07-03T15:55:12-05:00] upserted rows conflicts=0 duration=2.212807ms proposed=16 target="\"molt_movies\".\"USERS\".\"CUSTOMER_DEVICE\"" upserted=16
~~~
</section>

Expand Down
6 changes: 3 additions & 3 deletions src/current/_includes/molt/fetch-data-load-output.md
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Original file line number Diff line number Diff line change
Expand Up @@ -88,13 +88,13 @@

<section class="filter-content" markdown="1" data-scope="postgres">
~~~ json
{"level":"info","type":"summary","fetch_id":"f5cb422f-4bb4-4bbd-b2ae-08c4d00d1e7c","num_tables":3,"tables":["migration_schema.employees","migration_schema.payments","migration_schema.payments"],"cdc_cursor":"0/3F41E40","net_duration_ms":6752.847625,"net_duration":"000h 00m 06s","time":"2024-03-18T12:30:37-04:00","message":"fetch complete"}
{"level":"info","type":"summary","fetch_id":"f5cb422f-4bb4-4bbd-b2ae-08c4d00d1e7c","num_tables":3,"tables":["migration_schema.employees","migration_schema.payments","migration_schema.payments"],"skipped_unmigratable_tables":[],"cdc_cursor":"0/3F41E40","net_duration_ms":6752.847625,"net_duration":"000h 00m 06s","time":"2024-03-18T12:30:37-04:00","message":"fetch complete"}
~~~
</section>

<section class="filter-content" markdown="1" data-scope="mysql">
~~~ json
{"level":"info","type":"summary","fetch_id":"f5cb422f-4bb4-4bbd-b2ae-08c4d00d1e7c","num_tables":3,"tables":["public.employees","public.payments","public.payments"],"cdc_cursor":"4c658ae6-e8ad-11ef-8449-0242ac140006:1-29","net_duration_ms":6752.847625,"net_duration":"000h 00m 06s","time":"2024-03-18T12:30:37-04:00","message":"fetch complete"}
{"level":"info","type":"summary","fetch_id":"f5cb422f-4bb4-4bbd-b2ae-08c4d00d1e7c","num_tables":3,"tables":["public.employees","public.payments","public.payments"],"skipped_unmigratable_tables":[],"cdc_cursor":"4c658ae6-e8ad-11ef-8449-0242ac140006:1-29","net_duration_ms":6752.847625,"net_duration":"000h 00m 06s","time":"2024-03-18T12:30:37-04:00","message":"fetch complete"}
~~~

{% if page.name contains "delta" %}
Expand All @@ -109,7 +109,7 @@

<section class="filter-content" markdown="1" data-scope="oracle">
~~~ json
{"level":"info","type":"summary","fetch_id":"f5cb422f-4bb4-4bbd-b2ae-08c4d00d1e7c","num_tables":3,"tables":["migration_schema.employees","migration_schema.payments","migration_schema.payments"],"cdc_cursor":"backfillFromSCN=26685444,scn=26685786","net_duration_ms":6752.847625,"net_duration":"000h 00m 06s","time":"2024-03-18T12:30:37-04:00","message":"fetch complete"}
{"level":"info","type":"summary","fetch_id":"f5cb422f-4bb4-4bbd-b2ae-08c4d00d1e7c","num_tables":3,"tables":["migration_schema.employees","migration_schema.payments","migration_schema.payments"],"skipped_unmigratable_tables":[],"cdc_cursor":"backfillFromSCN=26685444,scn=26685786","net_duration_ms":6752.847625,"net_duration":"000h 00m 06s","time":"2024-03-18T12:30:37-04:00","message":"fetch complete"}
~~~

{% if page.name contains "delta" %}
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26 changes: 13 additions & 13 deletions src/current/_includes/molt/phased-delta-failback-all-sources.md
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Expand Up @@ -388,15 +388,15 @@ Verify that Replicator is processing changes successfully. To do so, check the M
You should see periodic primary keepalive messages:

~~~
DEBUG [Aug 25 14:38:10] primary keepalive received ReplyRequested=false ServerTime="2025-08-25 14:38:09.556773 -0500 CDT" ServerWALEnd=0/49913A58
DEBUG [Aug 25 14:38:15] primary keepalive received ReplyRequested=false ServerTime="2025-08-25 14:38:14.556836 -0500 CDT" ServerWALEnd=0/49913E60
DEBUG [2025-08-25T14:38:10-05:00] primary keepalive received ReplyRequested=false ServerTime="2025-08-25 14:38:09.556773 -0500 CDT" ServerWALEnd=0/49913A58
DEBUG [2025-08-25T14:38:15-05:00] primary keepalive received ReplyRequested=false ServerTime="2025-08-25 14:38:14.556836 -0500 CDT" ServerWALEnd=0/49913E60
~~~

When rows are successfully replicated, you should see debug output like the following:

~~~
DEBUG [Aug 25 14:40:02] upserted rows conflicts=0 duration=7.855333ms proposed=1 target="\"molt\".\"public\".\"tbl1\"" upserted=1
DEBUG [Aug 25 14:40:02] progressed to LSN: 0/49915DD0
DEBUG [2025-08-25T14:40:02-05:00] upserted rows conflicts=0 duration=7.855333ms proposed=1 target="\"molt\".\"public\".\"tbl1\"" upserted=1
DEBUG [2025-08-25T14:40:02-05:00] progressed to LSN: 0/49915DD0
~~~
</section>

Expand All @@ -406,30 +406,30 @@ You should see binlog syncer connection and row processing:
~~~
[2025/08/25 15:29:09] [info] binlogsyncer.go:463 begin to sync binlog from GTID set 77263736-7899-11f0-81a5-0242ac120002:1-38
[2025/08/25 15:29:09] [info] binlogsyncer.go:409 Connected to mysql 8.0.43 server
INFO [Aug 25 15:29:09] connected to MySQL version 8.0.43
INFO [2025-08-25T15:29:09-05:00] connected to MySQL version 8.0.43
~~~

When rows are successfully replicated, you should see debug output like the following:

~~~
DEBUG [Aug 25 15:29:38] upserted rows conflicts=0 duration=1.801ms proposed=1 target="\"molt\".\"public\".\"tbl1\"" upserted=1
DEBUG [Aug 25 15:29:38] progressed to consistent point: 77263736-7899-11f0-81a5-0242ac120002:1-39
DEBUG [2025-08-25T15:29:38-05:00] upserted rows conflicts=0 duration=1.801ms proposed=1 target="\"molt\".\"public\".\"tbl1\"" upserted=1
DEBUG [2025-08-25T15:29:38-05:00] progressed to consistent point: 77263736-7899-11f0-81a5-0242ac120002:1-39
~~~
</section>

<section class="filter-content" markdown="1" data-scope="oracle">
When transactions are read from the Oracle source, you should see registered transaction IDs (XIDs):

~~~
DEBUG [Jul 3 15:55:12] registered xid 0f001f0040060000
DEBUG [Jul 3 15:55:12] registered xid 0b001f00bb090000
DEBUG [2025-07-03T15:55:12-05:00] registered xid 0f001f0040060000
DEBUG [2025-07-03T15:55:12-05:00] registered xid 0b001f00bb090000
~~~

When rows are successfully replicated, you should see debug output like the following:

~~~
DEBUG [Jul 3 15:55:12] upserted rows conflicts=0 duration=2.620009ms proposed=13 target="\"molt_movies\".\"USERS\".\"CUSTOMER_CONTACT\"" upserted=13
DEBUG [Jul 3 15:55:12] upserted rows conflicts=0 duration=2.212807ms proposed=16 target="\"molt_movies\".\"USERS\".\"CUSTOMER_DEVICE\"" upserted=16
DEBUG [2025-07-03T15:55:12-05:00] upserted rows conflicts=0 duration=2.620009ms proposed=13 target="\"molt_movies\".\"USERS\".\"CUSTOMER_CONTACT\"" upserted=13
DEBUG [2025-07-03T15:55:12-05:00] upserted rows conflicts=0 duration=2.212807ms proposed=16 target="\"molt_movies\".\"USERS\".\"CUSTOMER_DEVICE\"" upserted=16
~~~
</section>

Expand Down Expand Up @@ -732,8 +732,8 @@ On the target cluster, create a CockroachDB changefeed to send changes to MOLT R
1. Verify that Replicator is reporting incoming HTTP requests from the changefeed. To do so, check the MOLT Replicator logs. Since you enabled debug logging with `-v`, you should see periodic HTTP request successes:

~~~
DEBUG [Aug 25 11:52:47] httpRequest="&{0x14000b068c0 45 200 3 9.770958ms false false}"
DEBUG [Aug 25 11:52:48] httpRequest="&{0x14000d1a000 45 200 3 13.438125ms false false}"
DEBUG [2025-08-25T11:52:47-05:00] httpRequest="&{0x14000b068c0 45 200 3 9.770958ms false false}"
DEBUG [2025-08-25T11:52:48-05:00] httpRequest="&{0x14000d1a000 45 200 3 13.438125ms false false}"
~~~

These debug messages confirm successful changefeed connections to MOLT Replicator. You can disable verbose logging after verifying the connection.
Expand Down
1 change: 1 addition & 0 deletions src/current/molt/molt-fetch-commands-and-flags.md
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Expand Up @@ -57,6 +57,7 @@ This page lists the [MOLT Fetch]({% link molt/molt-fetch.md %}) commands and the
| <a id="metrics-listen-addr"></a> `--metrics-listen-addr` | Address of the Prometheus metrics endpoint, which has the path `{address}/metrics`. For details on important metrics to monitor, refer to [Monitoring]({% link molt/molt-fetch-monitoring.md %}).<br><br>**Default:** `'127.0.0.1:3030'` |
| <a id="mode"></a> `--mode` | Configure the MOLT Fetch behavior: `data-load`, `export-only`, or `import-only`. For details, refer to [Fetch mode]({% link molt/molt-fetch.md %}#define-fetch-mode).<br><br>**Default:** `data-load` |
| <a id="non-interactive"></a> `--non-interactive` | Run the fetch task without interactive prompts. This is recommended **only** when running `molt fetch` in an automated process (i.e., a job or continuous integration). |
| <a id="opt-out-telemetry"></a> `--opt-out-telemetry` | Suppress MOLT telemetry-event logging, which is enabled by default. |
| <a id="pglogical-replication-slot-name"></a> `--pglogical-replication-slot-name` | Name of a PostgreSQL replication slot that will be created before taking a snapshot of data. Must match the slot name specified with `--slotName` in the [MOLT Replicator command]({% link molt/molt-replicator.md %}#replication-checkpoints). For details, refer to [Initial bulk load (before replication)]({% link molt/molt-fetch.md %}#initial-bulk-load-before-replication). |
| <a id="pglogical-publication-and-slot-drop-and-recreate"></a> `--pglogical-publication-and-slot-drop-and-recreate` | Drop the PostgreSQL publication and replication slot if they exist, then recreate them. Creates a publication named `molt_fetch` and the replication slot specified with `--pglogical-replication-slot-name`. For details, refer to [Initial bulk load (before replication)]({% link molt/molt-fetch.md %}#initial-bulk-load-before-replication).<br><br>**Default:** `false` |
| <a id="pprof-listen-addr"></a> `--pprof-listen-addr` | Address of the pprof endpoint.<br><br>**Default:** `'127.0.0.1:3031'` |
Expand Down
6 changes: 3 additions & 3 deletions src/current/molt/molt-fetch.md
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Expand Up @@ -767,13 +767,13 @@ A change data capture (CDC) cursor is written to the MOLT Fetch output as `cdc_c
For MySQL:

~~~ json
{"level":"info","type":"summary","fetch_id":"735a4fe0-c478-4de7-a342-cfa9738783dc","num_tables":1,"tables":["public.employees"],"cdc_cursor":"b7f9e0fa-2753-1e1f-5d9b-2402ac810003:3-21","net_duration_ms":4879.890041,"net_duration":"000h 00m 04s","time":"2024-03-18T12:37:02-04:00","message":"fetch complete"}
{"level":"info","type":"summary","fetch_id":"735a4fe0-c478-4de7-a342-cfa9738783dc","num_tables":1,"tables":["public.employees"],"skipped_unmigratable_tables":[],"cdc_cursor":"b7f9e0fa-2753-1e1f-5d9b-2402ac810003:3-21","net_duration_ms":4879.890041,"net_duration":"000h 00m 04s","time":"2024-03-18T12:37:02-04:00","message":"fetch complete"}
~~~

For Oracle:

~~~ json
{"level":"info","type":"summary","fetch_id":"735a4fe0-c478-4de7-a342-cfa9738783dc","num_tables":3,"tables":["migration_schema.employees"],"cdc_cursor":"backfillFromSCN=26685444,scn=26685786","net_duration_ms":6752.847625,"net_duration":"000h 00m 06s","time":"2024-03-18T12:37:02-04:00","message":"fetch complete"}
{"level":"info","type":"summary","fetch_id":"735a4fe0-c478-4de7-a342-cfa9738783dc","num_tables":3,"tables":["migration_schema.employees"],"skipped_unmigratable_tables":[],"cdc_cursor":"backfillFromSCN=26685444,scn=26685786","net_duration_ms":6752.847625,"net_duration":"000h 00m 06s","time":"2024-03-18T12:37:02-04:00","message":"fetch complete"}
~~~

This `cdc_cursor` value is also included in the output of a fetch task from a PostgreSQL source. However, in the case of a PostgreSQL source, you can instead enable replication with the [`--pglogical-replication-slot-name`]({% link molt/molt-fetch-commands-and-flags.md %}#pglogical-replication-slot-name) and [`--pglogical-publication-and-slot-drop-and-recreate`]({% link molt/molt-fetch-commands-and-flags.md %}#pglogical-publication-and-slot-drop-and-recreate) flags, which must be defined.
Expand Down Expand Up @@ -1031,7 +1031,7 @@ molt fetch \
The output will include a `cdc_cursor` value at the end of the fetch task:

~~~ json
{"level":"info","type":"summary","fetch_id":"735a4fe0-c478-4de7-a342-cfa9738783dc","num_tables":1,"tables":["public.employees"],"cdc_cursor":"b7f9e0fa-2753-1e1f-5d9b-2402ac810003:3-21","net_duration_ms":4879.890041,"net_duration":"000h 00m 04s","time":"2024-03-18T12:37:02-04:00","message":"fetch complete"}
{"level":"info","type":"summary","fetch_id":"735a4fe0-c478-4de7-a342-cfa9738783dc","num_tables":1,"tables":["public.employees"],"skipped_unmigratable_tables":[],"cdc_cursor":"b7f9e0fa-2753-1e1f-5d9b-2402ac810003:3-21","net_duration_ms":4879.890041,"net_duration":"000h 00m 04s","time":"2024-03-18T12:37:02-04:00","message":"fetch complete"}
~~~

<section class="filter-content" markdown="1" data-scope="mysql oracle">
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12 changes: 6 additions & 6 deletions src/current/molt/replicator-metrics.md
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Expand Up @@ -439,17 +439,17 @@ replicator start \
If successful, Replicator will start, and the console output will indicate that the snapshotter has started as well:

~~~
INFO [Feb 2 10:20:32] Replicator starting
INFO [2026-02-02T10:20:32-05:00] Replicator starting
...
INFO [Feb 2 10:20:32] metrics snapshotter started, writing to replicator-data/metrics-snapshots every 15s, retaining 168h0m0s
INFO [2026-02-02T10:20:32-05:00] metrics snapshotter started, writing to replicator-data/metrics-snapshots every 15s, retaining 168h0m0s
~~~

Upon interruption of Replicator, the snapshotter will be stopped:

~~~
INFO [Feb 2 10:26:45] Interrupted
INFO [Feb 2 10:26:45] metrics snapshotter stopped
INFO [Feb 2 10:26:45] Server shutdown complete
~~~
INFO [2026-02-02T10:26:45-05:00] Interrupted
INFO [2026-02-02T10:26:45-05:00] metrics snapshotter stopped
INFO [2026-02-02T10:26:45-05:00] Server shutdown complete
~~~

#### Step 2. Find the snapshot files in the data directory
Expand Down
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