regex - Reg exp to match a specific HTTP response code in apache or nginx server logs

Question

I am looking for a regexp that could match a specific response code (error code) in apache or nginx webserver logs.

10.80.248.64 - - [02/Nov/2012:15:04:40 +0000] "GET //browse/OS HTTP/1.1" 404 497 "-" "-"
10.220.64.11 - - [02/Nov/2012:15:04:54 +0000] "GET / HTTP/1.0" 200 491 "-" "Wget/1.12 (linux-gnu)"
10.80.16.66 - - [29/Oct/2012:11:09:11 +0000] "GET / HTTP/1.1" 302 0 "-" "Mozilla/5.0 (Macintosh; Intel Mac OS X 10.8; rv:7.0.1) Gecko/20100101 Firefox/7.0.1" 

The reg exp should be able to match lines with a specific error code like 404, 200 or 302.

Answer 1

Use regex pattern

^[^"]*"[^"]*\sHTTP\/[\d.]+"\s+(?:200|302|404)\s.*$
 └─┬─┘│└─┬─┘└┤└────┬─────┘│└┬┘└──────┬──────┘└┤└┤
   │  │  │   │     │      │ │        │        │ │
   │  │  │   │     │      │ │        │        │ └─ anything (including nothing)
   │  │  │   │     │      │ │        │        │ 
   │  │  │   │     │      │ │        │        └─ one space (white-space character)
   │  │  │   │     │      │ │        │
   │  │  │   │     │      │ │        └─ 200 or 302 or 404
   │  │  │   │     │      │ │
   │  │  │   │     │      │ └─ one or more spaces (white-space characters)
   │  │  │   │     │      │
   │  │  │   │     │      └─ one double-quote character
   │  │  │   │     │
   │  │  │   │     └─ HTTP/ followed by a combination of digit(s) and/or dot(s)
   │  │  │   │
   │  │  │   └─ one space (white-space character) 
   │  │  │
   │  │  └─ anything (including nothing) but double-quote character(s)
   │  │
   │  └─ one double-quote character
   │
   └─ anything (including nothing) but double-quote character(s)