NimbostratusHello, I am trying to save public IPs with an iRule by using the hostname and mapping it to the pool. The rule came from here but I can't find the original thread but it seems to work but I wanted to make sure it is the most efficient way to do it.
NimbostratusThanks for the help in advance!
The datagroup will be string and be formated like hostname:poolname
when HTTP_REQUEST {
test_dg is a string data-group where the entries are name:value pairs
name is the requested HTTP host header, value is the associated pool-name
check the requested HTTP host header against entries in data-group
if { [class match [string tolower [HTTP::host]] equals test_dg ] } {
if the HTTP host header is in datagroup
send the request to the pool associated with the datagroup entry
pool [class match -value [string tolower [HTTP::host]] equals test_dg ]
} else {
drop the request if the host header is not in datagroup
drop
}
}
CirrocumulusLooks good to me, there is very little to optimize here.
Reading directly from a variable like [HTTP::host] is faster than setting the value in a variable and read that variable after. However, in this case, you are also using the string tolower twice, so not sure if there will be any improvement.
when HTTP_REQUEST {
test_dg is a string data-group where the entries are name:value pairs
name is the requested HTTP host header, value is the associated pool-name
check the requested HTTP host header against entries in data-group
set host [string tolower [HTTP::host]]
if { [class match $host equals test_dg ] } {
if the HTTP host header is in datagroup
send the request to the pool associated with the datagroup entry
pool [class match -value $host equals test_dg ]
} else {
drop the request if the host header is not in datagroup
drop
}
}
Have a look in this link about testing the speed of the iRule.
https://devcentral.f5.com/articles/irules-optimization-101-05-evaluating-irule-performance
If you want to read the full article:
https://devcentral.f5.com/articles/irules-optimization-101-01-if-elseif-and-switch