code 206 - visible as '206' in varnishncsa and as '200' from VCL code

[Laurence Rowe]

On 28 July 2011 16:37, Johnny Halfmoon <jhalfmoon at milksnot.com> wrote:
> Hi there,
>
> as a long time user of Varnish I still have an annoying little issue on my
> todo list: It seems that when returning partial content, Varnishnsca
> properly logs the transfer with a code 206 'partial content', but logging
> the exact same transfer from VCL code, it returns code '200', which is
> incorrect. I have tried using VRT_r_obj_status, VRT_r_rest_status and
> VRT_r_beresp status to no avail. This is the case with both Varnish 2.1.5
> and 3.0.0. Is this done on purpose by the code or can it be registered as a
> bug?
>
> This is how I test it (examples using Varnish 3.0.0):
>
> #=== The command to do the RANGE request (note the returncode 206 'partial
> content) ===
>
> testproxy02 ~ # http_proxy=http://127.0.0.1:80 curl -v -r 500-1000
> http://vi.nl
> .
> .
>>
>> Proxy-Connection: Keep-Alive
>>
> < HTTP/1.1 206 Partial Content
> < Server: Apache
> .
> ...<output truncated>...
>
> #=== This is the output of varnishncsa (note the code '206')===
>
> testproxy02 ~ # varnishncsa
> 127.0.0.1 - - [28/Jul/2011:17:17:23 +0200] "GET http://bla.nlhttp://bla.nl
> HTTP/1.1" 206 501 "-" "curl/7.15.5 (x86_64-redhat-linux-gnu) libcurl/7.15.5
> OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5"
>
> #=== This is the output I get in syslog (note the code '200') ===
>
> testproxy02 ~ # tail -f /var/log/varnish/current
>  code:200
>  127.0.0.1 - - "Thu, 28 Jul 2011 15:16:56 GMT" "GET http://bla.nl" 200 58944
> "-" "curl/7.15.5 (x86_64-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b
> zlib/1.2.3 libidn/0.6.5" X:616508938 B:bla_nl V:bla.nl h:1
>
> #=== This is the bit of inline C code used to do the loggin from VCL ===
>
> int mycode = VRT_r_resp_status(sp);
> if (mycode == NULL) { mycode = 0; }
> syslog(LOG_DEBUG, "code:%u ", mycode );
> .
> ...<output truncated>...
>
> #=== EOF ===

I believe Varnish makes the request to the backend without the Range
header, so the result may still be cached. I'm not familiar enough
with the VRT commands to know exactly what you are logging, but if it
is the backend response code then you would expect that to be 200 (as
it would not have seen the Range header.)

Laurence