Disappearing logs?

[gljiva]

Hi, we have a client that is experiencing indexed log disappearing and reappearing on a daily basis. Log input is a file that gets populated by custom application, all logs follow splunk log recommendation (one line with nice timestamp). Logs get indexed and one day you can see them, another day they just disappear. Indexer is a Windows 2008_64 server. Any suggestions how to troubleshoot this, or ideas how can this happen? There is no custom processing of logs, no scripted preprocessing, no sed filtering...

[Genti]

This sounds quite impossible. Are you sure you are running the same exact search every time? Time frame is the same as well? same user running the searches?
Is it specific to some index, all indexes? Some Sources, all sources? etc..

[gljiva]

Search is sourcetype based, time is specified as custom time and is bound to specific date (in past), I will upload screenshots that shows exacly how on timeline it is evident that logs dissapear and reappear.