Linux – In tail -f, how to filter out stuff that has certain keywords

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I want to tail -f my logs. However, I want to filter out everything that has the words:

"ELB", "Pingdom", "Health"

Best Answer

I don't know about using awk instead of grep, but this works for me:

tail -f file.log | grep -Ev '(ELB|Pingdom|Health)'

EDIT: As dmourati and Caleb pointed out, you could also use egrep instead of grep -E for convenience. On some systems this this will be an link to the same binary, in others a copy of it supplied by the grep package. Either way it lives as an alternative to the -E switch. However, according to the GNU grep man page:

[…]two variant programs egrep and fgrep are available. egrep is the same as grep -E. fgrep is the same as grep -F. Direct invocation as either egrep or fgrep is deprecated, but is provided to allow historical applications that rely on them to run unmodified.

Since they are synonymous commands, it comes down to preference unless you don't have egrep at all. However for forward compatibility it is recommended to use the grep -E syntax since the other method is officially deprecated.

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