Okay, your code is like this...
sourcetype=fgt devname=loc1 OR devname=loc2 OR devname=loc3
| eval Bytes=len(_raw)
| eval Date=strftime(_time,"%Y-%m-%d")
| eval GB=(Bytes/(1024*1024*1024))
| chart span=1d sum(GB) over devname by Date limit=0
The above should always give results when the following conditions are true
1) there are events in sourcetype=fgt with devname=loc1 OR devname=loc2 OR devname=loc3
2) field _raw exists in the events.
3) the events have a valid _time.
4) the events are on an index that you have access to read. (YOU SHOULD ALWAYS CODE "index=foo")
5) the search has time to complete.
I suspect the problem is item 5.
To test items 1-4, run this in verbose mode...
sourcetype=fgt with devname=loc1 OR devname=loc2 OR devname=loc3
| head 1
| eval Bytes=len(_raw)
| eval Date=strftime(_time,"%Y-%m-%d")
| eval GB=(Bytes/(1024*1024*1024))
If the above search generates no results, then there is an error in the search code. Perhaps the fields have been renamed since the original search was coded, or perhaps you have lost security access to the index.
If there are results, then verify that Bytes, Date and GB all have valid values. If they do, then the problem is probably that your scheduled search ran out of time before it could complete.
Check the job for messages. I believe you can open the scheduled search (the empty results) and then use the job inspector to look for messages.
There are a couple of ways to extend the search time, but we'll explore your followup question first, since tstats , if workable, is a better use of machine time.
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