运行Varnish 4，我偶尔会得到503错误，我不能把我的手指。我已经尝试直接curl后端，它每次都会返回一个响应，所以它不看起来像问题在那里。 下面是从我的varnishlog入口，但它没有告诉我很多。 我通过运行命令获得了这个日志
varnishlog -q "RespStatus >= 500 or BerespStatus >= 500"
这是日志条目
* << Request >> 524356 - 524356 Begin c req 524355 rxreq - 524356 Timestamp c Start: 1421453220.095464 0.000000 0.000000 - 524356 Timestamp c Req: 1421453220.095464 0.000000 0.000000 - 524356 ReqStart c 173.255.199.52 38213 - 524356 ReqMethod c GET - 524356 ReqURL c /asd/asdasd - 524356 ReqProtocol c HTTP/1.0 - 524356 ReqHeader c X-Real-IP: 206.169.79.151 - 524356 ReqHeader c Host: www.CENSORED.com - 524356 ReqHeader c X-Forwarded-For: 206.169.79.151 - 524356 ReqHeader c X-Time-Server-Received: 1421453197 - 524356 ReqHeader c Connection: close - 524356 ReqHeader c Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8 - 524356 ReqHeader c User-Agent: Mozilla/5.0 (Macintosh; Intel Mac OS X 10_10_1) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/39.0.2171.99 Safari/537.36 - 524356 ReqHeader c Accept-Encoding: gzip, deflate, sdch - 524356 ReqHeader c Accept-Language: en-US,en;q=0.8 - 524356 ReqHeader c Cookie: wp-settings-1=deleted%3Dundefined%26ed_size%3D1305%26hidetb%3D1%26libraryContent%3Dbrowse%26editor%3Dtinymce%26imgsize%3Dlarge%26wplink%3D1%26urlbutton%3Dfile%26pos ts_list_mode%3Dlist; wp-settings-time-1=1421309968; wp-saving-post=5-saved; wordpr - 524356 ReqUnset c X-Forwarded-For: 206.169.79.151 - 524356 ReqHeader c X-Forwarded-For: 206.169.79.151, 173.255.199.52 - 524356 VCL_call c RECV - 524356 ReqUnset c Cookie: wp-settings-1=deleted%3Dundefined%26ed_size%3D1305%26hidetb%3D1%26libraryContent%3Dbrowse%26editor%3Dtinymce%26imgsize%3Dlarge%26wplink%3D1%26urlbutton%3Dfile%26pos ts_list_mode%3Dlist; wp-settings-time-1=1421309968; wp-saving-post=5-saved; wordpr - 524356 ReqHeader c Cookie: wp-settings-1=deleted%3Dundefined%26ed_size%3D1305%26hidetb%3D1%26libraryContent%3Dbrowse%26editor%3Dtinymce%26imgsize%3Dlarge%26wplink%3D1%26urlbutton%3Dfile%26pos ts_list_mode%3Dlist; wp-settings-time-1=1421309968; wp-saving-post=5-saved; wordpr - 524356 ReqUnset c Cookie: wp-settings-1=deleted%3Dundefined%26ed_size%3D1305%26hidetb%3D1%26libraryContent%3Dbrowse%26editor%3Dtinymce%26imgsize%3Dlarge%26wplink%3D1%26urlbutton%3Dfile%26pos ts_list_mode%3Dlist; wp-settings-time-1=1421309968; wp-saving-post=5-saved; wordpr - 524356 ReqHeader c Cookie: wp-settings-1=deleted%3Dundefined%26ed_size%3D1305%26hidetb%3D1%26libraryContent%3Dbrowse%26editor%3Dtinymce%26imgsize%3Dlarge%26wplink%3D1%26urlbutton%3Dfile%26pos ts_list_mode%3Dlist; wp-settings-time-1=1421309968; wp-saving-post=5-saved; wordpr - 524356 VCL_return c pass - 524356 VCL_call c HASH - 524356 VCL_return c lookup - 524356 VCL_call c PASS - 524356 VCL_return c fetch - 524356 Link c bereq 524357 pass - 524356 Timestamp c Fetch: 1421453222.583956 2.488493 2.488493 - 524356 Timestamp c Process: 1421453222.583983 2.488520 0.000027 - 524356 RespHeader c Date: Sat, 17 Jan 2015 00:07:02 GMT - 524356 RespHeader c Server: Varnish - 524356 RespHeader c X-Varnish: 524356 - 524356 RespProtocol c HTTP/1.1 - 524356 RespStatus c 503 - 524356 RespReason c Service Unavailable - 524356 RespReason c Service Unavailable - 524356 VCL_call c SYNTH - 524356 RespHeader c Content-Type: text/html; charset=utf-8 - 524356 RespHeader c Retry-After: 5 - 524356 VCL_return c deliver - 524356 RespHeader c Content-Length: 415 - 524356 Debug c "RES_MODE 2" - 524356 RespHeader c Connection: close - 524356 Timestamp c Resp: 1421453222.584031 2.488567 0.000048 - 524356 ReqAcct c 983 0 983 205 415 620 - 524356 End c
我的default.vcl
vcl 4.0; import std; backend default { .host = "localhost"; .port = "81"; .connect_timeout = 600s; .first_byte_timeout = 600s; .between_bytes_timeout = 600s; } acl purge { # Only allow purges coming from localhost "127.0.0.1"; "localhost"; }
编辑：varnishstat同时抛出503错误。 你可以看到fetch_failed发生了很多次。
MAIN.uptime 787 1.00 1.00 1.00 1.00 MAIN.sess_conn 11076 10.99 14.00 8.30 8.17 MAIN.client_req 11089 11.98 14.00 8.40 8.23 MAIN.cache_hit 1488 1.00 1.00 1.32 1.41 MAIN.cache_hitpass 2 0.00 . 0.00 0.00 MAIN.cache_miss 3186 1.00 4.00 1.27 1.29 MAIN.backend_conn 9585 9.99 12.00 7.01 6.76 MAIN.backend_reuse 17 1.00 . 0.16 0.12 MAIN.backend_recycle 17 1.00 . 0.16 0.12 MAIN.fetch_head 2 0.00 . 0.06 0.06 MAIN.fetch_length 346 2.00 . 0.39 0.35 MAIN.fetch_chunked 4497 3.99 5.00 2.27 2.06 MAIN.fetch_close 4756 4.99 6.00 4.36 4.35 MAIN.fetch_failed 180 0.00 . 0.10 0.12 MAIN.pools 4 0.00 . 4.00 4.00 MAIN.threads 54 0.00 . 54.00 54.00 MAIN.threads_limited 1 0.00 . 0.00 0.00 MAIN.threads_created 102 0.00 . 0.00 0.00 MAIN.threads_destroyed 48 0.00 . 0.00 0.00 MAIN.busy_sleep 5 0.00 . 0.00 0.00 MAIN.busy_wakeup 5 0.00 . 0.00 0.00 MAIN.sess_queued 50 0.00 . 0.00 0.00 MAIN.n_object 2873 1.00 . 2866.32 2865.00 MAIN.n_objectcore 2891 1.00 . 2885.40 2884.22 MAIN.n_objecthead 2990 1.00 . 2981.80 2980.00 MAIN.n_backend 1 0.00 . 1.00 1.00 MAIN.n_expired 135 0.00 . 133.18 132.78 MAIN.s_sess 11076 10.99 14.00 8.30 8.17 MAIN.s_req 11089 11.98 14.00 8.40 8.23 MAIN.s_pass 6415 9.99 8.00 5.81 5.52 MAIN.s_fetch 9601 10.99 12.00 7.09 6.82 MAIN.s_synth 112 0.00 . 0.00 0.00 MAIN.s_req_hdrbytes 3346583 3583.50 4252.00 2308.12 2251.15 MAIN.s_req_bodybytes 804869 1072.65 1022.00 202.52 162.86 MAIN.s_resp_hdrbytes 2737544 3615.46 3478.00 1942.75 1857.93 MAIN.s_resp_bodybytes 66853226 14104.28 84946.00 37816.96 38189.12 MAIN.sess_closed 9442 6.99 11.00 6.96 7.05 MAIN.backend_req 9594 10.99 12.00 7.17 6.87
守护程序选项
DAEMON_OPTS="-a :80 \ -f /etc/varnish/default.vcl \ -T 127.0.0.1:6082 \ -u varnish -g varnish \ -t 120 \ -n $INSTANCE \ -s malloc,10G \ -p thread_pools=4 \ -p thread_pool_min=5 \ -p thread_pool_max=500 \ -p thread_pool_timeout=300 \ -S /etc/varnish/secret"
有什么build议么？
503错误发生时，您的清漆处理了多less个请求/总数和总连接？
我遇到类似的情况，它会返回503错误的用户，而后端运行得很好。
varnishlog将显示后台实际上是健康的病态。
所以经过一番挖掘，我发现问题是最大的文件描述符。
我不得不增加我的系统的最大文件描述符，以便清漆能够正确处理所有请求。
之后，所有的503错误都停止了，所有的后端都显示健康。
请增加所有的内核限制：最大文件打开，最大进程文件和。 如果你使用的是像centos这样的linux base radhat，编辑两个文件：/etc/security/limit.conf
你不会看到在清漆日志中，清漆503意味着没有后端，所以你当时需要监视/ var / log / messages和Apache，Nginx，PHP错误日志。 后端在请求期间遇到错误，varnish不能进一步处理请求。 所以清漆不知道那里正在发生什么事情，它不必，这不是他的事情。
顺便说一句，尝试从光油推荐的设置开始：
-p thread_pool_min=200 \ -p thread_pool_max=4000 \ -p thread_pool_add_delay=2 \ -p http_req_size=64000 \ -p cli_timeout=25 \ -p cli_buffer=36384 \ -p session_linger=100 \ -s malloc,(YOURMEMORY-20%)G
而这行是sysctl.conf中的一个必须项：
fs.file-max = 700000
这些也是：
echo "* soft nofile 200000" >> /etc/security/limits.conf echo "* hard nofile 700000" >> /etc/security/limits.conf