Here is an updated iRule (F5-iRule-dhcp_mac_sticky(June 2016).txt) which is not yet updated to guide...
# iRule dhcp_mac_sticky rev 0.5 (2016/05/23)
#
# Written By: Shun Takahashi
# Updated By: Jay Cedrone (2014)
# Updated By: Craig Hyps (2015)
# Updated By: Brad Parker (2016)
#
# Original By: Jun Chen (j.chen at f5.com)
# Original At: https://devcentral.f5.com/community/group/aft/25727/asg/50
#
# RFC2131 defines DHCP packet structure. This irule is to scan
# UDP payload and store information into session tables with
# your_mac as a key.
#
# Requirement: The rule requires virtual server to listen on DHCP traffic in the
# middle either in inline or out of band.
#
# 1) In-Line to DHCP traffic
#
# profile udp udp_dhcp {
# allow-no-payload disabled
# app-service none
# datagram-load-balancing disabled
# idle-timeout immediate
# ip-tos-to-client 0
# link-qos-to-client 0
# proxy-mss disabled
# }
#
# ltm virtual vs_dhcp {
# destination 0.0.0.0:bootps
# ip-protocol udp
# mask any
# profiles {
# udp_dhcp { }
# }
# rules {
# dhcp_mac_sticky
# }
# source 0.0.0.0/0
# translate-address disabled
# vlans {
# local
# }
# vlans-enabled
# }
#
# 2) Receiving mirrored DHCP stream
#
# References: RFC 2132 DHCP Options and BOOTP Vendor Extensions
# RFC 1533 DHCP Options and BOOTP Vendor Extensions (Obsoleted)
# RFC 4702 The Dynamic Host Configuration Protocol (DHCP) Client
# Fully Qualified Domain Name (FQDN) Option
#
timing off
when RULE_INIT {
# Rule Name and Version shown in the log
set static::RULE_NAME "DHCP MAC Sticky v0.5"
set static::RULE_ID "dhcp_mac_sticky"
# 0: No Debug Logging 1: Debug Logging
set static::debug 0
# Persist timeout (seconds)
set static::persist_ttl 7200
}
when CLIENT_ACCEPTED priority 100 {
# Using High-Speed Logging in thie rule
set log_prefix "\[$static::RULE_ID\]([IP::client_addr])"
set log_prefix_d "$log_prefix\(debug\)"
if {$static::debug}{log local0.debug "$log_prefix_d ***** iRule: $static::RULE_NAME executed *****"}
if { [UDP::payload length] < 200 } {
log local0.info "$log_prefix Ignored due to length\(less than 200 octet\)"
drop
return
}
else {
# BOOTP
binary scan [UDP::payload] ccccH8SB1xa4a4a4a4H2H2H2H2H2H2 \
msg_type hw_type hw_len hops transaction_id seconds\
bootp_flags client_ip_hex your_ip_hex server_ip_hex \
relay_ip_hex m(a) m(b) m(c) m(d) m(e) m(f)
# Put client address into variables for session key
set your_ip [IP::addr $your_ip_hex mask 255.255.255.255]
set client_mac "$m(a):$m(b):$m(c):$m(d):$m(e):$m(f)"
binary scan [UDP::payload] H32H64H128H8 \
padding server_host_name boot_file magic_cookie
if {$static::debug}{log local0.debug "$log_prefix_d BOOTP: $your_ip $client_mac"}
# DHCP
binary scan [UDP::payload] x240H* dhcp_option_payload
set option_hex 0
set options_length [expr {([UDP::payload length] -240) * 2 }]
for {set i 0} {$i < $options_length} {incr i [expr { $length * 2 + 2 }]} {
# extract option value and convert into decimal
# for human readability
binary scan $dhcp_option_payload x[expr $i]a2 option_hex
set option [expr 0x$option_hex]
# move index to get length field
incr i 2
# extract length value and convert length from Hex string to decimal
binary scan $dhcp_option_payload x[expr $i]a2 length_hex
set length [expr 0x$length_hex]
# extract value field in hexadecimal format
binary scan $dhcp_option_payload x[expr $i + 2]a[expr { $length * 2 }] value_hex
switch $option {
61 {
# Client Identifier
# This option is used by DHCP clients to specify their unique
# identifier. DHCP servers use this value to index their database of
# address bindings. This value is expected to be unique for all
# clients in an administrative domain.
#
binary scan $value_hex a2a* ht id
switch $ht {
01 {
binary scan $id a2a2a2a2a2a2 m(a) m(b) m(c) m(d) m(e) m(f)
# Normalize MAC address to upper case
set value [string toupper "$m(a)-$m(b)-$m(c)-$m(d)-$m(e)-$m(f)"]
}
default {
set value "$id"
}
}
persist uie $value $static::persist_ttl
# if {$static::debug}{log local0.debug "$log_prefix_d ***** iRule: $static::RULE_NAME completed ***** OPTION61=$value TARGET=[persist lookup uie $value]"}
if {$static::debug}{log local0.debug "$log_prefix_d ***** iRule: $static::RULE_NAME completed ***** OPTION61=$value TARGET=[persist lookup uie "$value any virtual"]"}
}
}
}
}
}
thank you very much.