Tracking requests through Varnish servers

[Ben Dodd]

Hello,

I'd like to be able to track the progress of a request as it passes through multiple Varnish servers (using each other as backends).

What is the best way to do this? I've tried using +=, but this is not acceptable for strings (failed to compile). Currently I have multiple headers as follows but is there a way of concatenating them into a single string?

set resp.http.X-Cache-v1 = "MISS"
set resp.http.X-Cache-v2 = "HIT"

Thanks, Ben

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