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Active connection spikes on some backend servers

Hi everyone, we are seeing an issue wherein the number of active connections on the backend servers is spiking from time to time (> 50K). This apparently happens only on one of the backend servers (out of the 9 servers) at a time. The server with the spike keeps switching and there is no consistency. All other servers show < 1K connections during this time. I do not have access to the logs or all the configs as of now (will get this from the Ops team), but does anyone have any idea why this could be happening? Any help will be greatly appreciated.

The backend config looks like the following (I’ve obfuscated some parts):

backend CONFIG1
balance roundrobin
option http-keep-alive
timeout http-keep-alive 10m
option httpchk GET /xxxxx
http-check expect rstatus 200
http-reuse always
bind-process 11 12
server SERVER01 10.xx.y.zz:80 check weight 10
server SERVER02 10.xx.y.zz:80 check weight 10
server SERVER03 10.xx.y.zz:80 check weight 10
server SERVER04 10.xx.y.zz:80 check weight 10
server SERVER05 10.xx.y.zz:80 check weight 10
server SERVER06 10.xx.y.zz:80 check weight 10
server SERVER07 10.xx.y.zz:80 check weight 10
server SERVER08 10.xx.y.zz:80 check weight 10