Http header

I have URL xyz.abc.com now when client hits this URL ..F5 should insert http header with server name ,which server request should be forwarded .

do you want to manually select server and insert custom http header based on hostname in url (host header)?

or

do you want to rewrite http host header based on load balanced server?

this is an example of the latter one.

 config

root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm virtual bar
ltm virtual bar {
    destination 172.28.24.10:80
    ip-protocol tcp
    mask 255.255.255.255
    pool foo
    profiles {
        http { }
        tcp { }
    }
    rules {
        qux
    }
    source 0.0.0.0/0
    source-address-translation {
        type automap
    }
    vs-index 7
}
root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm pool foo
ltm pool foo {
    members {
        200.200.200.101:80 {
            address 200.200.200.101
        }
        200.200.200.111:80 {
            address 200.200.200.111
        }
    }
}
root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm data-group internal servername
ltm data-group internal servername {
    records {
        200.200.200.101/32 {
            data server101
        }
        200.200.200.111/32 {
            data server111
        }
    }
    type ip
}
root@(ve11a)(cfg-sync In Sync)(Active)(/Common)(tmos) list ltm rule qux
ltm rule qux {
    when HTTP_REQUEST_SEND {
  clientside {
    HTTP::header replace Host [class lookup [LB::server addr] servername]
  }
}
}

 trace

[root@ve11a:Active:In Sync] config  ssldump -Aed -nni 0.0 port 80
New TCP connection 1: 172.28.24.1(38986) - 172.28.24.10(80)
1409877091.1710 (0.0015)  C>S
---------------------------------------------------------------
GET /attempt1 HTTP/1.1
User-Agent: curl/7.15.5 (i686-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5
Host: 172.28.24.10
Accept: */*

---------------------------------------------------------------

New TCP connection 2: 200.200.200.14(38986) - 200.200.200.111(80)
1409877091.5871 (0.4142)  C>S
---------------------------------------------------------------
GET /attempt1 HTTP/1.1
User-Agent: curl/7.15.5 (i686-redhat-linux-gnu) libcurl/7.15.5 OpenSSL/0.9.8b zlib/1.2.3 libidn/0.6.5
Host: server111
Accept: */*

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