tcpdump_at_varnish.md

### tcpdumpでHeaderを可視化するで。特定backendとの通信を見てみよか。
$ /usr/sbin/tcpdump -i bond0.2168 -s 3000 -A dst host <対象backendのIP> or src host <対象backendのIP>

################### passナシ
...!..3.GET /kakeru.css HTTP/1.1
User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.13.1.0 zlib/1.2.3 libidn/1.18 libssh2/1.2.2
Host: 10.10.10.10
Accept: */*
X-Forwarded-For: 10.10.10.10
X-Varnish: 1299767291
Accept-Encoding: gzip  ################### ついてる、、、


18:38:37.816571 IP 対象backendのIP.http > 10.10.10.10.10783: Flags [.], ack 289, win 486, options [nop,nop,TS val 2328703874 ecr 3400524833], length 0
E..41.@.>.1.
...
....P...C...`.............
..3....!
18:38:37.816755 IP 対象backendのIP.http > 10.10.10.10.10: Flags [P.], seq 1:1138, ack 289, win 486, options [nop,nop,TS val 2328703874 ecr 3400524833], length 1137
E...1.@.>.-k
...
....P...C...`.......*.....
..3....!HTTP/1.1 200 OK
Server: nginx
Date: Mon, 05 Oct 2015 09:38:37 GMT
Content-Type: text/css
Last-Modified: Mon, 01 Aug 2011 02:24:27 GMT
Transfer-Encoding: chunked  ################### chunkedや、、、
Connection: keep-alive
ETag: W/"4e360e5b-5fb"
Expires: Sun, 03 Jan 2016 09:38:37 GMT
Cache-Control: max-age=7776000
Content-Encoding: gzip

###################  passアリ
......P#V.?.o.O.....o.....
........GET /kakeru.css HTTP/1.1
User-Agent: curl/7.19.7 (x86_64-redhat-linux-gnu) libcurl/7.19.7 NSS/3.13.1.0 zlib/1.2.3 libidn/1.18 libssh2/1.2.2
Host: 10.10.10.10*/*
X-Varnish: 1299767296
 ################### なにもついてない、、、


18:40:27.347718 IP 対象backendのIP.http > 10.10.10.10s [.], ack 233, win 486, options [nop,nop,TS val 2329012463 ecr 3400634364], length 0
E..47.@.>.+.
...
....P...o.O#W.'....ac.....
........
18:40:27.347751 IP 対象backendのIP.http > 10.10.10.10.46869: Flags [.], seq 1:1449, ack 233, win 486, options [nop,nop,TS val 2329012463 ecr 3400634364], length 1448
E...7.@.>.&.
...
....P...o.O#W.'...........
........HTTP/1.1 200 OK
Server: nginx
Date: Mon, 05 Oct 2015 09:40:27 GMT
Content-Type: text/css
Content-Length: 1531 ################### Content-Lengthや、、、
Last-Modified: Mon, 01 Aug 2011 02:24:27 GMT
Connection: keep-alive
ETag: "4e360e5b-5fb"
Expires: Sun, 03 Jan 2016 09:40:27 GMT
Cache-Control: max-age=7776000
Accept-Ranges: bytes
kakerukaeru/tcpdump_at_varnish.md
