CSS - Sticky via HTTP Header

[Sbutzek]

Hello,

There is an application with an app-Proxy between the Application Server and the Client.

Client -> Proxy -> App Server

So i have two proxy Servers, which intercept the client requests and then forward them to the Application Servers.

There are 4 Application Servers, and Stickyness is needed, that the Client Session always terminate on the same Application Server.

I can not use Source-IP because i have only 2 Proxy Servers.

The Application Proxy, does add a Header in the HTTP Request to the Application Server, which contains the client ip Address, which startet the request to the Proxy.

Is it possible to do a Stickyness via a Hader named client_ip which contains the original Client IP Adresses?

I do not know the Client-IP Address, because it is an Internet Application.

I think, if the client_ip is a cookie i can do this via changing the string operation hash-crc32.

But i never tried this.

Sven

[Gilles Dufour]

Sven,

I don't think you can stick on data that are in the header. You can if the data are in the url or in a cookie. I don't think this is the case here.

Could you use arrowpoint-cookies ??

This would work.

Gilles.

[Sbutzek]

Hi Gilles,

i think best is, the Server will put a Cookie.

Using arrowpint-cookies i never did, and i think this will cost some more performance vs the server.

The new ACE Module can stick via Header strings i've seen.

Sven

[Gilles Dufour]

Yes the ACE module can stick on header data.

This is a new hardwrae with a new software.

Gilles.

[Norberto Salgado]

Hi,

anyone have a configuration example of stikyness for http header data?

I searched but Im unable to find one...

Thank you.

Best regards,

Norberto

[Pablo]

Hi Norberto,

This is a basic configuration for stickiness based on HTTP headers.

sticky http-header Accept-Charset head-sticky
timeout 10
serverfarm Standard

class-map type http loadbalance match-any L7-URL
2 match http url .*.htm

policy-map type loadbalance first-match L7-match
class L7-URL
sticky-serverfarm head-sticky
class class-default
serverfarm default

A common header field when dealing with proxy'd connections is the X-Forwarded-For:

sticky http-header X-Forwarded-For Src-IP
timeout 10
serverfarm Backend

HTH

__ __

Pablo

[Norberto Salgado]

Hi,

Thank you Pablo.

This feature of do stickyness by the http header data it's only available in ACEs or also its supported in CSM?

Best regards,

Norberto

[Pablo]

Hi Norberto,

Sure the CSM is also able to stick clients based on HTTP header, here is a config snippet:

MSFC-A(config)# module csm 2

MSFC-A(config-module-csm)# sticky 7 header X-Forwarded-For timeout 20
MSFC-A(config-slb-sticky-header)# header offset 5 length 50

vserver Web

virtual 192.168.78.35 tcp 80

serverfarm Backend

sticky 20 group 7

persistent rebalance

inservice

HTH =)

__ __

Pablo