Jun 14, 2012
tom

Custom VCL prevents varnish from starting

Question

Operating System: CentOS 6 (x86_64)

I have installed and configured varnish however it now is unable to start.

# service varnish restart
Stopping Varnish Cache:                                    [FAILED]
Starting Varnish Cache:                                    [FAILED]

I have narrowed this error down to the inclusion of another VCL file in /etc/varnish/default.vcl.

I include the VCL like so:

include "/etc/varnish/domains/playwithbits.vcl";

If I empty the contents of playwithbits.vcl then varnish is able to start, but as soon as I add contents it fails.

The contents of my playwithbits.vcl are:

backend playwithbits {
     .host = "localhost";
     .port = "8080";
}
acl purge {
     if (req.http.Host ~ "playwithbits.com") {
          "localhost";
     }
}
sub vcl_recv {
     if (req.http.Host ~ "playwithbits.com") {
          set req.backend = playwithbits; 
          if (req.request == "PURGE") {
               if (!client.ip ~ purge) {
                    error 405 "Not allowed.";
               }
               return(lookup);
          }
          if (req.url ~ "^/$") {
               unset req.http.cookie;
          }
     }
}
sub vcl_hit {
     if (req.http.Host ~ "playwithbits.com") {
          if (req.request == "PURGE") {
               set obj.ttl = 0s;
                    error 200 "Purged.";
          }
     }
}
sub vcl_miss {
     if (req.http.Host ~ "playwithbits.com") {
          if (req.request == "PURGE") {
               error 404 "Not in cache.";
          } 
          if (!(req.url ~ "wp-(login|admin)")) {
               unset req.http.cookie;
          }
          if (req.url ~ "^/[^?]+.(jpeg|jpg|png|gif|ico|js|css|txt|gz|zip|lzma|bz2|tgz|tbz|html|htm)(\?.|)$") {
               unset req.http.cookie;
               set req.url = regsub(req.url, "\?.$", "");
          }
          if (req.url ~ "^/$") {
               unset req.http.cookie;
          }
     }
}
sub vcl_fetch {
     if (req.http.Host ~ "playwithbits.com") {
          if (req.url ~ "^/$") {
               unset beresp.http.set-cookie;
          }
          if (!(req.url ~ "wp-(login|admin)")) {
               unset beresp.http.set-cookie;
          }
     }
}

Here is the output of # strace -e trace=file service varnish start

execve("/sbin/service", ["service", "varnish", "start"], [/* 20 vars */]) = 0
access("/etc/ld.so.preload", R_OK)      = 0
open("/etc/ld.so.preload", O_RDONLY)    = 3
open("/etc/ld.so.cache", O_RDONLY)      = 3
open("/lib64/libtinfo.so.5", O_RDONLY)  = 3
open("/lib64/libdl.so.2", O_RDONLY)     = 3
open("/lib64/libc.so.6", O_RDONLY)      = 3
open("/dev/tty", O_RDWR|O_NONBLOCK)     = 3
open("/usr/lib/locale/locale-archive", O_RDONLY) = 3
open("/proc/meminfo", O_RDONLY)         = 3
stat("/etc/varnish", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
stat(".", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
open("/usr/lib64/gconv/gconv-modules.cache", O_RDONLY) = 3
open("/sbin/service", O_RDONLY)         = 3
open("/etc/init.d/functions", O_RDONLY) = 3
--- SIGCHLD (Child exited) @ 0 (0) ---
stat("/etc/sysconfig/i18n", {st_mode=S_IFREG|0644, st_size=47, ...}) = 0
open("/dev/null", O_WRONLY|O_CREAT|O_TRUNC, 0666) = 3
open("/etc/profile.d/lang.sh", O_RDONLY) = 3
stat("/root/.i18n", 0x7fff831f79e0)     = -1 ENOENT (No such file or directory)
stat("/etc/sysconfig/init", {st_mode=S_IFREG|0644, st_size=1153, ...}) = 0
open("/etc/sysconfig/init", O_RDONLY)   = 3
open("/usr/share/locale/locale.alias", O_RDONLY) = 3
open("/usr/share/locale/en_US.UTF-8/LC_MESSAGES/initscripts.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en_US.utf8/LC_MESSAGES/initscripts.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en_US/LC_MESSAGES/initscripts.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en.UTF-8/LC_MESSAGES/initscripts.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en.utf8/LC_MESSAGES/initscripts.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
open("/usr/share/locale/en/LC_MESSAGES/initscripts.mo", O_RDONLY) = -1 ENOENT (No such file or directory)
--- SIGCHLD (Child exited) @ 0 (0) ---
--- SIGCHLD (Child exited) @ 0 (0) ---
chdir("/")                              = 0
stat("/etc/init.d/varnish", {st_mode=S_IFREG|0755, st_size=2837, ...}) = 0
stat(".", {st_mode=S_IFDIR|0755, st_size=4096, ...}) = 0
stat("/sbin/env", 0x7fff831f8960)       = -1 ENOENT (No such file or directory)
stat("/usr/sbin/env", 0x7fff831f8960)   = -1 ENOENT (No such file or directory)
stat("/bin/env", {st_mode=S_IFREG|0755, st_size=23832, ...}) = 0
stat("/bin/env", {st_mode=S_IFREG|0755, st_size=23832, ...}) = 0
access("/bin/env", X_OK)                = 0
stat("/bin/env", {st_mode=S_IFREG|0755, st_size=23832, ...}) = 0
access("/bin/env", R_OK)                = 0
stat("/bin/env", {st_mode=S_IFREG|0755, st_size=23832, ...}) = 0
stat("/bin/env", {st_mode=S_IFREG|0755, st_size=23832, ...}) = 0
access("/bin/env", X_OK)                = 0
stat("/bin/env", {st_mode=S_IFREG|0755, st_size=23832, ...}) = 0
access("/bin/env", R_OK)                = 0
Starting Varnish Cache:                                    [FAILED]
--- SIGCHLD (Child exited) @ 0 (0) ---

Does anyone know what this issue is?

Asked by George Reith

Answer

Start varnish with a good config (default.vcl?), and then try running a syntax check on your VCL before loading it. In varnish v2.1 (assuming similar in 3.x):

$ varnishadm -T 127.0.0.1:6082 vcl.load error <path_to_your_vcl>
Answered by KM01

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