LB::select hangs

My workaround was similar to dig's Instead of using LB::select I got hook after the member is selected ("when LB_SELECTED") and then call LB:detach & LB::reselect

but in my irule i use LB::select to generate a token , which will be further used to persist connection ltm rule myirule { when HTTP_REQUEST { pool my-host-pool if {[HTTP::header exists LB-TOKEN]}{ set sid [HTTP::header value "LB-TOKEN"] log local0. "sid = $sid" if { $sid = "null" }{ log local0. "SID NULL !" set hex_sid "" scan [LB::select] %s%s%s%s%d command current_pool command2 current_member current_port scan [ split $current_member "." ] "%d%d%d%d" ip1 ip2 ip3 ip4 set ip3_hex [format "%02x" $ip3] set ip4_hex [format "%02x" $ip4] set port_hex [format "%04x" $current_port] append hex_sid $ip3_hex $ip4_hex $port_hex log local0. "hex_sid = $hex_sid , modifying header" HTTP::header replace "LB-TOKEN" $hex_sid log local0. "header_sid_value = [HTTP::header value LB-TOKEN] $current_member $current_port" pool $pool_name member $current_member $current_port } else { persist uie $sid } } }