String command necessary with advanced-balance arrowpoint-cookie on CSS?

[net-harry]

Hi,

I have a question regarding the use of "advance-balance arrowpoint-cookie" for sticky load balancing.

My question is whether the string command is necessary in the service in order for sticky load-balancing to work? We noticed recently that it say in the CSS Load-Balancing Configuration Guide that:

"The syntax and options for this content mode command are:
• advanced-balance arrowpoint-cookie - Enables the content rule to stick a
client to a server based on the unique service identifier information of the
selected server in the arrowpoint cookie. Configure the service identifier by
using the (config-service) string command".

We have never used the strings command for existing services and I therefore wonder if we need to change all our services (with content rules that use "advance-balance arrowpoint-cookie") to use the strings command as below:

service Service-1
  protocol tcp
  port 80
  keepalive type tcp
  keepalive port 80
  ip address 10.10.11.101
  string CSS-Service-1
  active

service Service-2
  protocol tcp
  port 80
  keepalive type tcp
  keepalive port 80
  ip address 10.10.11.102

  string CSS-Service-2
  active

owner Customer-A
  content Content-1
    vip address 10.10.10.10
    balance aca
    advanced-balance arrowpoint-cookie
    protocol tcp
    port 80
    url "/*"
    add service Service-1
    add service Service-2
    active

Thanks in advance for your help!

Best regards,

Harry

[Sean Merrow]

Hi Harry,

Your current configuration without the strings is fine, and also the most commonly used configuration.  When using advanced-balance cookie on the CSS, you are using cookie-insert.  The CSS will insert a cookie into the HTTP header of the server's response and if the client returns with new connection containing that cookie, the CSS will stick to the same server.  If you look at the value of the cookie inserted, it will contain the IP address of the server it was load balanced to.  Some customers don't not like this for various reasons.  If you include the string in the services, then the string will be used as the cookie value.

Hope this helps.

Sean