Question about No Nodes Available Rule

Improved version -

To take Joe's example one step further, you could use an array to count the errors per pool and only report the error every 50 times within each pool that fails (as opposed to every 50 times any pool fails).

when RULE_INIT {
    Initialize the counter to 0.
   array set ::log_ctr { }
}
when LB_FAILED {
   if { [LB::server addr] eq "" } {
      set pool [LB::server]
      if { not [info exists ::log_ctr($pool)] or $::log_ctr($pool) >= 50 } {
         log "No nodes available - pool $pool"
         set ::log_ctr($pool) 0
      } else {
         incr ::log_ctr($pool)
      }
   }
}