On 29 Apr 2016 06:55, "Willy Tarreau" <w...@1wt.eu> wrote: > > On Fri, Apr 22, 2016 at 04:37:04PM +0200, Erwin Schliske wrote: > > Hello, > > > > for some of our services requests pass haproxy twice. As we have set the > > global option unique-id-header this header is added twice. [snip] > > I don't know what could cause this. Would you happen to have it in a > defaults section maybe, with your traffic passing through a frontend > and a backend ? If that's what causes it, I think we have a mistake > in the implementation and should ensure it's done only once, just like > x-forwarded-for.
I /think/ you're talking at slight cross-porpoises! My reading of the OP is that when a request comes in to a frontend/listener with the configured unique-Id header already present, then a second UID header is added. My reading of your post, Willy, is that this would be a bug (which might suggest why unique-id-header isn't ACL-able?). But I may have misunderstood - you may be talking solely about when a request crosses a frontend/backend boundary, and not when the request comes in the front door anew (even if it was, as per the OP, a request coming back in directly from a backend). Am I right, both? I only ask because this has bugged me slightly in the past, and it'd be great to clear up the definition of the UID header option: When enabled, is the header's addition predicated on its initial absence? J
