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Forum Discussion

lstewart_53611's avatar
lstewart_53611
Icon for Nimbostratus rankNimbostratus
Apr 21, 2010

Limiting number of connected clients

I am trying to write a rule to limit the number of individual clients that can connect to a VS, but not limit the total number of connections that they can have. After that limit has been reached, ad...
application delivery
dev
devops
iRules
nitass's avatar
nitass
Icon for Employee rankEmployee
Nov 15, 2011
i revised the table command's example a little bit. may it be usable? 

[root@ve1023:Active] config  b virtual bar list
virtual bar {
   snat automap
   pool foo
   destination 172.28.65.152:ssh
   ip protocol tcp
   rules myrule
}
[root@ve1023:Active] config  b rule myrule list
rule myrule {
   when CLIENT_ACCEPTED {
   event CLIENT_CLOSED disable

set tbl "clientlimit"
set key "[IP::client_addr]"

        log local0. "[IP::client_addr]:[TCP::client_port]|[table keys -subtable $tbl]|[table keys -subtable $tbl -count]"

        if {[table lookup -subtable $tbl $key] equals ""} {
                if {[table keys -subtable $tbl -count] > 0} {
                        reject
                        log local0. "[IP::client_addr]:[TCP::client_port] is rejected"
                } else {
                        table set -subtable $tbl $key "ignored" 180
                        set timer [after 60000 -periodic {table lookup -subtable $tbl $key}]
                        event CLIENT_CLOSED enable
                }
        }
}

when CLIENT_CLOSED {
    after cancel $timer
    table delete -subtable $tbl $key
}
}

[root@ve1023:Active] config  tail -f /var/log/ltm
Nov 15 08:27:58 local/tmm info tmm[4766]: Rule myrule : 192.168.204.7:53985||0
Nov 15 08:28:05 local/tmm info tmm[4766]: Rule myrule : 192.168.204.7:53989|192.168.204.7|1
Nov 15 08:28:15 local/tmm info tmm[4766]: Rule myrule : 192.168.204.7:53991|192.168.204.7|1
Nov 15 08:28:24 local/tmm info tmm[4766]: Rule myrule : 172.28.17.30:56279|192.168.204.7|1
Nov 15 08:28:24 local/tmm info tmm[4766]: Rule myrule : 172.28.17.30:56279 is rejected