: PostgreSQL Online Backup

Hello Everyone,

We have had situations where-in "rsync" was executed without executing
"pg_start_backup()" on the production data directory and on the next runs,
"pg_start_backup()" has been executed with "rsync". This was to avoid high
IO load on production. We ended up getting unmatched files (especially in
pg_clog) and not sure about "base" directory.

Postgres is asking for WAL Archive files dated sometime around 15 days ago.
We are absolutely not sure whats going on.

Is this dangerous for production (like corruption) ? or just the backup will
be invalid ? Please help us know if we have to perform any precautionary
checks on the production cluster.

Apart from firing a checkpoint, does "pg_start_backup()" updates any
dictionary tables or views ? or it updates anything in "pg_xlog"

Looking forward for your help !

Thanks
VB