HSL iRule is failing

I'm using BIG-IP VE 11.6.0HF4.

I cannot get HSL to work.

My syslog_server_pool is fine - I can see its UDP probes'

default send string

on remote SYSLOG server.

When I send traffic, /var/log/ltm shows:

Aug 10 17:25:49 BigIP-A info tmm[15093]: Rule /Common/hsl_SERVER_CONNECTED : Active members: 1, HSL handle is 'MDS:/Common/syslog_server_pool:UDP'; send result is '0'
Aug 10 17:25:49 BigIP-A info tmm[15093]: Rule /Common/hsl_SERVER_CONNECTED : 99.99.99.2:59012 -> 66.66.66.2:80 ::: 88.88.88.2:59012 -> 99.99.99.2:80

but no

Test

string is sent to the remote SYSLOG server (I confirmed this using tcpdump) and as you can see above, result

0

- why?

R's, Alex

root@(BigIP-A)(cfg-sync Standalone)(Active)(/Common)(tmos.ltm.virtual) list v.Client1.http
ltm virtual v.Client1.http {
    destination 66.66.66.2:http
    ip-protocol tcp
    mask 255.255.255.255
    pool c.Client1.http
    profiles {
        http { }
        tcp { }
    }
    rules {
        hsl_SERVER_CONNECTED
    }
    source 0.0.0.0/0
    source-address-translation { type automap }
    vs-index 3
}
root@(BigIP-A)(cfg-sync Standalone)(Active)(/Common)(tmos.ltm.rule) list hsl_SERVER_CONNECTED
ltm rule hsl_SERVER_CONNECTED {
   when SERVER_CONNECTED {
     set pool syslog_server_pool
     set hsl [HSL::open -proto UDP -pool $pool]
     set res [HSL::send $hsl "Test\n"]
     log local0. "Active members: [active_members $pool], HSL handle is '$hsl'; send result is '$res'"
     log local0. "[IP::client_addr]:[TCP::client_port] -> [clientside {IP::local_addr}]:[clientside {TCP::local_port}] ::: [serverside {IP::local_addr}]:[serverside {TCP::local_port}] -> [IP::server_addr]:[serverside {TCP::remote_port}]"
   }
}
root@(BigIP-A)(cfg-sync Standalone)(Active)(/Common)(tmos.ltm.pool) list syslog_server_pool
ltm pool syslog_server_pool {
    members {
        loghost1-net:514 {
            address XX.XX.XX.XX
            session monitor-enabled
            state up
        }
    }
    monitor udp 
}

root@(BigIP-A)(cfg-sync Standalone)(Active)(/Common)(tmos.ltm.pool) show syslog_server_pool

---------------------------------------------------------------------
Ltm::Pool: syslog_server_pool          
---------------------------------------------------------------------
Status                                 
  Availability : available             
  State        : enabled               
  Reason       : The pool is available 
  Monitor      : udp                   
  Minimum Active Members : 0           
  Current Active Members : 1           
          Total Requests : 0           
        Current Sessions : 0           
                                       
Traffic                                  ServerSide
  Bits In                                         0
  Bits Out                                        0
  Packets In                                      0
  Packets Out                                     0
  Current Connections                             0
  Maximum Connections                             0
  Total Connections                               0
                                       
Connection Queue                               Pool  Pool and members
  Number of connections queued now                0                 0
  Number of connections serviced                  0                 0
  Queue head entry age (ms)                       0                 0
  Maximum queue entry age ever (ms)               0                 0
  Maximum queue entry age recently (ms)           0                 0
  Average queue entry age (ms)                    0                 0