I am trying to find commands executed on my xen server yesterday - but the oldest command to be seen with history dates from today. Is there a way to see older commands (history displays 380 latest commands on my server)?
I'm afraid your yesterday's history is gone (if not within the 380 lines).
Just guessing: Your
HISTFILESIZE shell variable is set to around that value. That's "the maximum number of lines contained in the history file." (man bash) which persist across logout / logins. Try setting higher.