Passing through client IP address to server

Dag-Erling Smørgrav des at
Fri Jun 8 16:11:40 CEST 2007

"ADOFMS Admin, SteveOC" <admin at> writes:
> There is also a HTTP_X_VIA being set sometimes, which reports the
> hostname of the client machine. This variable isnt set on every request
> though.

X-Via most likely comes from a downstream cache, possibly a client-side
Squid cache or something similar.

> There is also a HTTP_X_VARNISH variable set as well, which is just a
> number.  Any idea what this one does ?

It is a reference to the internal request ID, which is recorded in the
log file.  For a cache hit, X-Varnish will contain both the ID of the
current request and the ID of the request that populated the cache.  It
makes debugging Varnish a *lot* easier.

Dag-Erling Smørgrav
Senior Software Developer
Linpro AS -

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