---
id: runbook-local-table-data-server
title: Local Table Data Server runbook
---

The [Local Table Data Server (LTDS)](../core-components/local-table-data-service.md) is an optional Deephaven process (`db_ltds`) that serves intraday table data from the local filesystem over the table data service (TDS) protocol. It is no longer started as part of the default installation, but remains available for deployments that need to publish local data as a network service or offload read traffic from other table data providers.

## Impact of Local Table Data Server failure

| Level            | Impact                                                                                                                                                                         |
| :--------------- | :----------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Sev 2 - Moderate | If the LTDS is configured in the routing, then any data it serves will not be available. Intraday data served by this LTDS will be inaccessible until the service is restored. |

> [!NOTE]
> LTDS is optional. If not configured in routing, its failure has no impact. The severity depends on how critical the data it serves is to operations.

## Local Table Data Server dependencies

The LTDS requires:

1. **Configuration Server** — Must be running to access table schemas and routing.
2. **Authentication Server** — Must be running for token validation.
3. **Filesystem access** — Must have read access to data storage paths.
4. **etcd cluster** — Must be accessible (via Configuration Server).

The LTDS does not depend on:

- Data Import Server
- Data tailers
- Write processes

## Checking Local Table Data Server status

Check process is running with monit:

```bash
dh_monit status db_ltds
```

Expected output should show status `Running`.

## Viewing Local Table Data Server logs

View application log:

```bash
cat /var/log/deephaven/ltds/LocalTableDataServer.log.current
```

Tail the log to follow in real-time:

```bash
tail -f /var/log/deephaven/ltds/LocalTableDataServer.log.current
```

List historical log files:

```bash
ls -ltr /var/log/deephaven/ltds/db_ltds.log.????-??-??
```

View process stdout/stderr logs:

```bash
cat /var/log/deephaven/ltds/db_ltds.log.$(date +%Y-%m-%d)
```

## Restart procedure

Restart the LTDS:

```bash
dh_monit restart db_ltds
```

**Impact:** Restarting LTDS will disconnect all clients reading data from this server. Clients will need to reconnect (often automatic via routing) and re-subscribe to tables.

Verify the restart was successful:

```bash
dh_monit status db_ltds
```

Monitor the log during startup:

```bash
tail -f /var/log/deephaven/ltds/LocalTableDataServer.log.current
```

## Routing configuration

LTDS loads its routing configuration from the `tableDataServices` section of the routing YAML. See [Table data services configuration](../configuration/yaml.md#table-data-services) for configuration details and [dhconfig routing command reference](../configuration/dhconfig/routing.md) for importing and exporting routing configuration.

## Configuration files and locations

**monit configuration:** `/etc/sysconfig/illumon.d/monit/db_ltds.conf`

**Property files:**

- `/etc/sysconfig/illumon.d/resources/iris-common.prop`
- Service-specific properties configured through `dhconfig`

**Data directory:** Configured per routing — LTDS serves intraday data from `/db/Intraday/<namespace>/<tableName>` on the local host

**Log directory:** `/var/log/deephaven/ltds/`

## Related documentation

- [Local Table Data Service overview](../core-components/local-table-data-service.md)
- [Table data services configuration](../configuration/yaml.md#table-data-services)
- [dhconfig routing command reference](../configuration/dhconfig/routing.md)
- [Process restart guide](../architecture/resilience-planning/process-restart-guide.md#local-table-data-server-ltds)
- [System processes overview](../architecture/architecture-overview.md)
- [Data Import Server runbook](runbook-data-import-server.md)
- [Configuration Server runbook](runbook-config-server.md)