Hi Joe, On Mon, Feb 18, 2019 at 05:48:09PM +0000, Joe K wrote: > https://github.com/haproxy/haproxy/blob/3d95717b58be0902078e0693e383bc32ea3a715a/src/proxy.c#L714 > seems like it's not possible, haproxy seems to be using `strcmp` without > expanding what's inside %[]. I wonder if it would be useful to anyone > beside me? > > On Mon, Feb 18, 2019 at 5:25 PM Joe K <[email protected]> wrote: > > > Hello everyone! > > > > > > I wonder if there is a way to use %[...] syntax in use-server directives. > > > > > > backend be_template > > server-template websrv 1-100 localhost:6666 check disabled > > use-server > > %[req.hdr(host),lower,map_dom(/usr/local/etc/haproxy/domain2server.map,websrv0)] > > if { req.hdr(host),lower,map_dom(/usr/local/etc/haproxy/domain2server.map) > > -m found } > > > > Right now, using the above makes haproxy fail at startup with the > > following error: > > > > > > haproxy_1 | [ALERT] 048/161559 (1) : config : backend 'be_template' : > > unable to find server > > '%[req.hdr(host),lower,map_dom(/usr/local/etc/haproxy/domain2server.map,websrv0)]' > > referenced in a 'use-server' rule. > > haproxy_1 | [ALERT] 048/161559 (1) : Fatal errors found in configuration. > > > > > > Just in case, I've also asked the same question on the forum: > > https://discourse.haproxy.org/t/in-use-server/3529 > >
Indeed it's not possible to parse a log-format string there. However, you can set dynamically the destination IP with 'http-request set-dst' and '0.0.0.0:0' as a server address. That's an ugly trick and that might be difficult to read logs and statistics when doing it because it will use the same server. -- William Lallemand
