503 is not available

Question

My version of varnish is 3.0 .

My server is working fine while I am twisting the urls, but when using the varnish cache, 503 service unavailable sometimes returned.

Information about the magazine is:

 0 Debug - "VCL_error(200, OK)" 24 VCL_call c recv error 24 VCL_call c error deliver 24 SessionClose c error 0 Debug - "VCL_error(200, OK)" 27 VCL_call c recv error 27 VCL_call c error deliver 27 SessionClose c error 0 Debug - "VCL_error(200, OK)" 16 VCL_call c recv error 16 VCL_call c error deliver 16 SessionClose c error 14 Debug - "Write error, retval = 2998272, len = 8465870, errno = Success" 0 Debug - "VCL_error(200, OK)" 14 VCL_call c recv error 14 VCL_call c error deliver 14 SessionClose c error 0 Debug - "VCL_error(200, OK)" 21 VCL_call c recv error 21 VCL_call c error deliver 21 SessionClose c error 

PS: Server 200 response when I freeze or type URLs in browsers.

Answer 1

503 can be removed using the following steps:

• Increase the values ​​of connect_timeout , .first_byte_timeout and .between_bytes_timeout in the backend settings:

   backend default { .host = "www.example.com"; .connect_timeout = 5s; .first_byte_timeout = 10s; .between_bytes_timeout = 10s; } 

• Increase the parameter to 8192 when starting the varnish.

   varnishd [options] http_resp_hdr_len=8192 

• Place an order for network or backend server .

  If steps 1 and 2 do not help you, please check the network connection and banckend server availability .