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Collector test error: "log_line_prefix not supported"

When you see output like this:

2018/05/20 19:56:18 I [server1] Testing statistics collection...
2018/05/20 19:56:20 I [server1] Test submission successful (15.9 KB received)
2018/05/20 19:56:20 I [server1] Testing local log tailing...
2018/05/20 19:56:20 E [server1] ERROR - Could not tail logs for server: Unsupported log_line_prefix setting: '%t '

It means that the currently configured log_line_prefix is not supported by the collector. You need to change your PostgreSQL configuration, reload the Postgres server, and then re-run pganalyze-collector --test.

Currently we support the following log_line_prefix settings when using Postgres built-in logging (log_destination = stderr):

  • log_line_prefix = '%m [%p] %q[user=%u,db=%d,app=%a] ' (recommended)
  • log_line_prefix = '%m [%p] %q[user=%u,db=%d,app=%a,host=%h] '
  • log_line_prefix = '%t:%r:%u@%d:[%p]:'
  • log_line_prefix = '%t [%p-%l] %q%u@%d '
  • log_line_prefix = '%t [%p]: [%l-1] user=%u,db=%d - PG-%e '
  • log_line_prefix = '%t [%p]: [%l-1] user=%u,db=%d,app=%a,client=%h '
  • log_line_prefix = '%t [%p]: [%l-1] [trx_id=%x] user=%u,db=%d '

The following are supported but not recommended, since they do not include the user name and database name:

  • log_line_prefix = '%m %r %u %a [%c] [%p] '
  • log_line_prefix = '%m [%p][%v] : [%l-1] %q[app=%a] '
  • log_line_prefix = '%m [%p] '

We also support the parsing of rsyslogd log lines that look like the following default template, with an empty log_line_prefix:

Feb  2 09:04:39 ip-172-31-14-41 postgres[7395]: [3-1] LOG:  database system is ready to accept connections

If you have a log_line_prefix config thats not covered, please reach out to us, as it is easy for us to add additional parsing support.

Collector test error: "permission denied"

When you see output like this:

2018/05/05 21:32:02 I [server1] Testing statistics collection...
2018/05/05 21:32:03 I [server1] Test submission successful (15.9 KB received)
2018/05/05 21:32:03 I [server1] Testing local log tailing...
2018/05/05 21:32:09 I [server1] Log test successful
2018/05/05 21:32:09 I Re-running log test with reduced privileges of "pganalyze" user (uid = 107, gid = 113)
2018/05/05 21:32:09 I [server1] Testing local log tailing...
2018/05/05 21:32:09 E [server1] ERROR - open /var/log/postgresql/postgresql-9.3-main.log: permission denied
2018/05/05 21:32:19 E [server1] ERROR - Could not tail logs for server: Timeout

It means that the log test was able to run successfully as a root user, but could not be completed when testing with the "pganalyze" user that the collector background process runs as.

See the appropriate instructions on moving the log directory out of the data directory or configuring syslog in the first step.

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