We have a F5 design were single Virtual Server (VIP) is pointing to multiple application on back-end via iRule & iRule load balancing is based on HTTP::host (Layer 7)
for eg:
when HTTP_REQUEST {
switch [string tolower [HTTP::host]] {
a.test.ae {
pool a_test_Pool1}
b.test.ae {
pool b_test_Pool1 }
}
}
We have a requirement to apply ASM policy on specific application (for eg: application "a") - while enforcing ASM policy specific to application "a" & applied on Virtual Server, will application "b" break? if so, please let me know what will be the best approach in this scenario.
17-Jan-202223:59 - last edited on 24-Mar-202201:21 by li-migration
Hi ,
If ASM policy has set any blocks/drops which matches traffic pattern coming for "application b" then yes, it will disturb that traffic also. So best approach would be applying ASM policy to specific or desired HOST URL only where you want to have it. You can achieve same using LTM policy.
Create LTM policy where under condition you can match HOST that you want to match for enabling ASM policy and then under actions -
ENABLE --> ASM --> Select desired ASM policy
Once you apply above LTM policy on the vServer, ASM policy will get applied to traffic coming for given host only.
applying ASM policy at virtual server level means that both application traffic will be seen by WAF:
Traffic learning will also show suggestions for b.test.ae in policy tuning
When policy is set to blocking state, traffic directed to b.test.ae will also be checked and will trigger protections, resulting in possible blocks.
iRule tool can manage ASM policy assignment.
I remember from installations I've performed, that you require an ASM policy to be applied at virtual server leve, regardless. You need to perform this task before modifying iRule or ASM instructions won't be accepted.
In your scenario, to prevent application b.test.ae to be checked by WAF, I'd just add an ASM::disable string instruction:
when HTTP_REQUEST {
switch [string tolower [HTTP::host]] {
a.test.ae {
pool a_test_Pool1}
b.test.ae {
ASM::disable
pool b_test_Pool1 }
}
}
