Karthik_Kumaran
Nimbostratus
NimbostratusLTM 11.4.1 - Trying to Identify equivalent features to cisco ACE
We have a legacy application which uses the following features in Cisco ACE parameter-map type http PARAMETERS case-insensitive persistence-rebalance set header-maxparse-length 65535 set content-maxparse-length 65535 length-exceed continue parsing non-strict
I am looking to find equivalents for these in F5 LTM as once we migrated the application to LTM we see a lot of intermittent issues accessing the application and a lot of 'Resets' from the clients to the Virtual Server IP in tcpdump.
The application has multiple pools and we are using the following irule to switch between pools based on a cookie that the application sends to the browser,
when CLIENT_ACCEPTED {
set default_pool [LB::server pool]
}
when HTTP_REQUEST {
ONECONNECT::reuse disable
if { [HTTP::cookie exists "Pool-cookie"] } {
switch [HTTP::cookie value "Pool-cookie"] {
"Pool1" {
pool Pool1
}
"Pool2" {
pool Pool2
}
default {
pool $default_pool
}
}
}
else {
pool $default_pool
}
}
- For the persitence-rebalance in ACE we are using Onceconnect, so the LTM can do L7 load-balancing decision for every HTTP request inside the same TCP connection (content switching feature of oneconnect). Just to ensure that the 'server-connection-resuse' is not causing any issues, it has been disabled inside the iRule. Effectively trying to use oneconnect only for the content switching requirement.
- the http header size has been set tp 65535 in the http_profile. the 'length-exceed continue' option ACE makes it still process the request even if the http header size is more that 65535, but i could not find a similar option to this in LTM. LTM sends a RST if the header size exceeds. Is there any option available in LTM similar to the 'length-exceed continue' feature in ACE???
- the 'parsing non-strict' in ACE, ignores malformed cookies in a request and continues parsing the remaining cookies. The application seems to have 'non-compliant RFC2396 characters' in its http responses, which the LTM might not like if it processes only RFC2396 compliant http requests. Is there any feature in LTM similar to the 'parsing non-strict' in ACE so it can continue process other cookies eventhough there are few malformed cookies from the application???
