restrict access Irule needed

It's a little unclear what you're trying to do, so I'll assume you only want to allow access the URL/VIP (abc.f5.com) from the two listed addresses - and that you want to use a data group to store those addresses. If that's the case:

1. Create an address-based data group. Example (my_ip_datagroup):

   10.1.11.49 mask 255.255.255.255 
   10.1.11.50 mask 255.255.255.255
   

2. Create an iRule like this:

   when CLIENT_ACCEPTED {
       if { not ( [class match [IP::client_addr] equals my_ip_datagroup] ) } {
           reject
       }
   }
   

You could also do this in a packet filter rule and prevent the 3-way handshake that the above iRule will allow.

i got one more , this will work ??

b class client_class '{ host 10.1.11.49 host 10.1.11.50 }'

b rule CLIENT_ACCEPTED_RULE '{ when HTTP_REQUEST { if { [matchclass [IP::remote_addr] equals $::client_class] } else { discard }} }'

b class alfaws_class '{ host 10.1.11.186.49 host 10.1.11.50 }'

b rule CLIENT_ACCEPTED_RULE '{ when HTTP_REQUEST { if { [matchclass [IP::remote_addr] equals $::alfaws_class] }{ pool abc.f5.corp.net } else { discard }} }'

That should work depending on your BIG-IP version. The matchclass command is deprecated in v11.

the version running in my LB is Version 10.2.4 771.0..i think it should work ???

The matchclass command will still work in v10.2, but you'll run into problems upgrading to v11. The new class commands will work in v10.2, however, so probably better to switch over now.

Ok thank will try and update you