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Some haproxy config examples

Here are some config snippets from the haproxy setup I mentioned in the last post.  Note that if this looks weird, it probably is - our environment is a bit of a mess, but due to constrained test resources, no cleanup is possible.

Some organizational helpers I used:

  • IP addresses 'make sense' - for example WEB02-IP2 is, -IP3 is .63, etc
  • Keep the naming convention for backends consistent
  • Keep things simple
  • Comments only for the first frontend, first backend, unless actual specific notes required
  • Keep spacing consistent, tabs, etc

Frontend Example

frontend domain1_com-http

# Subdomains: I put relevant subdomains here (just to keep track)
acl is_GKWEB-http hdr(host) -i -f /etc/haproxy/GKWEB-http-urls
# Subdomains: subdomain1 subdomain2
acl is_ITF01-http hdr(host) -i -f /etc/haproxy/ITF01-http-urls
# Subdomains: subdomain1 subdomain2
acl is_WEB34-IP2-http hdr(host) -i -f /etc/haproxy/WEB34-IP2-http-urls
# Subdomains: subdomain1 subdomain2
acl is_WEB02-IP2-http hdr(host) -i -f /etc/haproxy/WEB02-IP2-http-urls

use_backend GKWEB-http if is_GKWEB-http
use_backend ITF01-http if is_ITF01-http
use_backend WEB34-IP2-http if is_WEB34-IP2-http
use_backend WEB02-IP2-http if is_WEB02-IP2-http

default_backend maintenance

SFTP Backend

backend LG01-sftp
balance roundrobin
mode tcp
stick-table type ip size 200k expire 30m
stick on src
server lg01 check

Backend with IP Session Persistence

backend WEB02-IP2-http
balance roundrobin
# No persistence
server web02-ip2 check

backend WEB02-IP2-https
balance roundrobin
stick-table type ip size 200k expire 30m
stick on src
server web02-ip2 check ssl verify none

Backend with Cookie Session Persistence

backend WEB34-IP4-http
balance roundrobin
stick-table type ip size 200k expire 30m
stick on src
cookie SRV_ID prefix
server web03-ip4 check cookie
server web04-ip4 check cookie

backend WEB34-IP4-https
balance roundrobin
stick-table type ip size 200k expire 30m
stick on src
cookie SRV_ID prefix
server web03-ip4 check cookie ssl verify none
server web04-ip4 check cookie ssl verify none


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