Varnish still 503ing after adding grace to VCL

[Drew Smathers]

On Mon, Mar 7, 2011 at 5:39 PM, Per Buer <perbu at varnish-software.com> wrote:
> On Mon, Mar 7, 2011 at 9:58 PM, Drew Smathers <drew.smathers at gmail.com>
> wrote:
>>
>> Hi all,
>>
>> I'm trying to grace as a means of ensuring that cached content is
>> delivered from varnish past it's TTL if backends can't generate a
>> response.
>
> That's "Saint Mode" - please
> see http://www.varnish-cache.org/docs/trunk/tutorial/handling_misbehaving_servers.html#saint-mode
> I see that there isn't too much details on the semantics there. I'll see if
> I can add some details.

Hi Per,

I actually tried using saintmode for this problem but one point that I
found tricky is that saintmode (as far as i can tell from docs) can
only be set on beresp. If the backend is up, that's great because I
can check a non-200 status in vcl_fetch() and set. But in the case of
all backends being down, vcl_fetch() doesn't even get invoked and
there isn't any other routine and object in the routine's execution
context (that I know of) where I can set saintmode and restart.

Thanks,

-Drew