replace part of URI for specific URL and pass remaining

iRule It should be the following and any other additions can be added in a similar manner. You might consider speaking with the application team and have them perform the corrections on the server as this should only be done as a last resort in an iRule.

when CLIENT_ACCEPTED priority 500 {

    set DEFAULT_POOL [LB::server pool]

}

when HTTP_REQUEST priority 500 {

    if {[string tolower [HTTP::uri]] starts_with "/abc/defg/"} {
        HTTP::uri [string map {"/abc/defg/" "/uvw/xyz/"}[HTTP::uri]]
        pool pool_web
    } elseif {[string tolower [HTTP::uri]] starts_with "/123/456/"} {
        HTTP::uri [string map {"/123/456/" "/78/910/"}[HTTP::uri]]
        pool pool_web
    } elseif{[string tolower [HTTP::uri]] starts_with "/asdf-asdf/"} {
        HTTP::uri [string map {"/asdf-asdf/" "/lkjh-lkjh/"}[HTTP::uri]]
        pool pool_web
    } else {
        pool ${DEFAULT_POOL}
    }

}