iRule not working to have a RADIUS presistant load balancing.

Question

Hello All, &nbsp;I having trouble with an iRule that I created to load balance the RADIUS traffic on F5. I have a virtual server created that is listening on "all ports" and I have created an iRule in which it will only accept packets with ports 1812 &amp; 1813. This iRule is called in a Persistent profile I created (where parent profile is Universal). This Persistent profile was called under the Virtual server --resources--&gt; Default Persistent profile. &nbsp;Somehow this is it is not working for me. I see that the packets are reaching the F5 , but "Access-Request" packets are not being sent out to the pool members. iRule for reference is shown below :&nbsp;when RULE_INIT {&nbsp;array set ::attr_code2name { &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;1&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;User-Name&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;2&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;User-Password&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;3&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;CHAP-Password&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;4&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NAS-IP-Address&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;5&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NAS-Port&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;6&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Service-Type&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;7&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-Protocol&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;8&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-IP-Address&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;9&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-IP-Netmask&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;10&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-Routing&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;11&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Filter-Id&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;12&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-MTU&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;13&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-Compression&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;14&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Login-IP-Host&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;15&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Login-Service&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;16&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Login-TCP-Port&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;17&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(unassigned)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;18&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Reply-Message&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;19&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Callback-Number&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;20&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Callback-Id&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;21&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(unassigned)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;22&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-Route&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;23&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-IPX-Network&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;24&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;State&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;25&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Class&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;26&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Vendor-Specific&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;27&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Session-Timeout&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;28&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Idle-Timeout&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;29&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Termination-Action&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;30&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Called-Station-Id&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;31&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Calling-Station-Id&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;32&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NAS-Identifier&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;33&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Proxy-State&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;34&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Login-LAT-Service&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;35&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Login-LAT-Node&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;36&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Login-LAT-Group&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;37&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-AppleTalk-Link&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;38&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-AppleTalk-Network&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;39&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Framed-AppleTalk-Zone&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;60&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;CHAP-Challenge&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;61&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NAS-Port-Type&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;62&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Port-Limit&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;63&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Login-LAT-Port&nbsp;&nbsp;&nbsp;}}when CLIENT_ACCEPTED {&nbsp;&nbsp;if { ([UDP::local_port] != 1812) &amp;&amp; ([UDP::local_port] != 1813) } {&nbsp;&nbsp;&nbsp;log local0. "packet on port [UDP::local_port] dropped"&nbsp;&nbsp;&nbsp;drop&nbsp;&nbsp;}else {&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;set CALLID [RADIUS::avp 31 string]&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;persist uie $CALLID &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;log local0. "persisted $CALLID"&nbsp;&nbsp;}}when CLIENT_DATA {&nbsp;&nbsp;&nbsp;if { [UDP::local_port] == 1813 } {&nbsp;&nbsp;&nbsp;set CALLID [RADIUS::avp 31 string]&nbsp;&nbsp;&nbsp;set IP [RADIUS::avp 8 ip4]&nbsp;&nbsp;&nbsp;if { $IP != "" } {&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;table set $IP [LB::server addr] 900&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;log local0. "Radius maps $IP to [LB::server addr] for $CALLID"&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;}&nbsp;&nbsp;&nbsp;}}when LB_SELECTED {&nbsp;&nbsp;&nbsp;log local0. "Selected [LB::server addr] [LB::server port]"}when SERVER_DATA {&nbsp;&nbsp;&nbsp;persist add uie $CALLID&nbsp;&nbsp;&nbsp;log local0. "persist added for $CALLID to [LB::server addr]"}&nbsp;&nbsp;&nbsp;

enes_afsin_al · Answer

Hi ZANOOB,[RADIUS::avp 31 string] may be returning empty string. If empty, iRule will throw an error.Can you investigate the ltm logs and try this iRule?when CLIENT_DATA {
	if { [UDP::local_port] == 1813 } {
		set CALLID [RADIUS::avp 31 string]
		set IP [RADIUS::avp 8 ip4]
		if { $IP != "" } {
			table set $IP [LB::server addr] 900
			log local0. "Radius maps $IP to [LB::server addr] for $CALLID"
		}
	}
}
&nbsp;
when CLIENT_ACCEPTED {
	if { ([UDP::local_port] != 1812) &amp;&amp; ([UDP::local_port] != 1813) } {
		log local0. "packet on port [UDP::local_port] dropped"
		drop
	}
	elseif {
		set CALLID [RADIUS::avp 31 string]
		log local0. "persisted $CALLID"
		
		if { $CALLID ne "" } {
			persist uie $CALLID
		}
	}
}
&nbsp;
when CLIENT_DATA {
	if { [UDP::local_port] == 1813 } {
		set CALLID [RADIUS::avp 31 string]
		set IP [RADIUS::avp 8 ip4]
		if { $IP ne "" &amp;&amp; $CALLID ne "" } {
			table set $IP [LB::server addr] 900
			log local0. "Radius maps $IP to [LB::server addr] for $CALLID"
		}
	}
}
&nbsp;
when LB_SELECTED {
	log local0. "Selected [LB::server addr] [LB::server port]"
}
&nbsp;
when SERVER_DATA {
	if { $CALLID ne "" } {
		persist add uie $CALLID
		log local0. "persist added for $CALLID to [LB::server addr]"
	}
}

zanoob · Answer

Hello Enes Afsin Al, &nbsp;Thank you for your reply. Much appreciated. The above iRule, I was not able to save it since it shows some syntax errors. Not an expert in scripts, so couldn't find what is wrong with the syntax of it. -------------------------------01070151:3: Rule [/Common/CallIDUIE2] error: /Common/CallIDUIE2:17: error: [parse error: PARSE syntax 501 {syntax error in expression " set CALLID [RADIUS::avp 31 string] log local0. ...": variable references require preceding $}][{ set CALLID [RADIUS::avp 31 string] log local0. "persisted $CALLID"&nbsp; if { $CALLID ne "" } { persist uie $CALLID } }]/Common/CallIDUIE2:24: error: [missing a script after "elseif"][]/Common/CallIDUIE2:27: error: ["Duplicate event"][when CLIENT_DATA { if { [UDP::local_port] == 1813 } { set CALLID [RADIUS::avp 31 string] set IP [RADIUS::avp 8 ip4] if { $IP ne "" &amp;&amp; $CALLID ne "" } { table set $IP [LB::server addr] 900 log local0. "Radius maps $IP to [LB::server addr] for $CALLID" } } }]&nbsp;&nbsp;--------------------------------&nbsp;The packet capture shows the AVP 31 attribute  (&nbsp;Calling-Station-Id) in it.  So the issue is not the attribute value missing, however, something that F5 is not able to understand is the packet not processing it forwards. &nbsp;&nbsp;Frame 2: 317 bytes on wire (2536 bits), 317 bytes captured (2536 bits)Ethernet II, Src: Fortinet_09:00:12 (00:09:0f:09:00:12), Dst: VMware_f5:03:01 (00:50:56:f5:03:01)802.1Q Virtual LAN, PRI: 0, DEI: 0, ID: 4091Internet Protocol Version 4, Src: 172.17.70.60, Dst: 10.1.6.100User Datagram Protocol, Src Port: 54892, Dst Port: 1812RADIUS Protocol&nbsp;&nbsp;&nbsp;Code: Access-Request (1)&nbsp;&nbsp;&nbsp;Packet identifier: 0x5e (94)&nbsp;&nbsp;&nbsp;Length: 164&nbsp;&nbsp;&nbsp;Authenticator: e0a10849518a2fc1f0827505db9f8a5c&nbsp;&nbsp;&nbsp;Attribute Value Pairs&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=NAS-IP-Address(4) l=6 val=172.17.70.60&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=NAS-Port(5) l=6 val=0&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=NAS-Port-Type(61) l=6 val=Virtual(5)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=User-Name(1) l=15 val=mgalantowicza&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=User-Password(2) l=18 val=Encrypted&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=Service-Type(6) l=6 val=Shell-User(6)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=Calling-Station-Id(31) l=14 val=b0b867cd68ee&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Type: 31&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Length: 14&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Calling-Station-Id: b0b867cd68ee&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=Called-Station-Id(30) l=14 val=b0b867cd68ee&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=Vendor-Specific(26) l=23 vnd=Aruba, a Hewlett Packard Enterprise company(14823)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=Vendor-Specific(26) l=18 vnd=Aruba, a Hewlett Packard Enterprise company(14823)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVP: t=Message-Authenticator(80) l=18 val=a0d082620a1137f9110e2a5975c7d6a8F5 Ethernet Trailer Protocol&nbsp;&nbsp;However, I will check the LTM logs. But last time I checked it really didn't give any error for the virtual server. It simply is not forwarding the traffic, to the load-balanced Radius servers. &nbsp;&nbsp;

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iRule not working to have a RADIUS presistant load balancing.

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