This knowledge article provides solutions for cases when Syslog-ng Store Box (SSB) stops processing logs to logspaces.
1. A product defect exists in versions 5.0.1 where, after a reload of Syslog-ng, it stops processing logs.
2. There is an inaccessible remote destination in a flow-control enabled logpath.
This issue was fixed in version 5.0.2 of Syslog-ng Store Box.
Please upgrade to version latest 5 LTS version or to 6 LTS to resolve this issue.
In this case, after starting of syslog-ng the message collection works fine until the output buffers of the inaccessible destination get full. Then flow-control kicks in and stops reading the sources, so no messages are processed to the logspaces.
Basically there are three options.