交换机-主机拓扑链路追踪脚本，使用 shell 语法完成

switch-host-linkmap.sh

#!/bin/bash


# ============================================================
# related links: 
#   http://www.cisco.com/c/en/us/support/docs/ip/simple-network-management-protocol-snmp/13492-cam-snmp.html
# ============================================================

# ============  related MIB/OIDs =============================
# CISCO-CDP-MIB::cdpCacheDeviceId
# CISCO-CDP-MIB::cdpCacheDevicePort

# SNMPv2-MIB::sysName.0
# IF-MIB::ifName
# BRIDGE-MIB::dot1dBasePortIfIndex
# CISCO-VTP-MIB::vtpVlanState
# VALN: BRIDGE-MIB::dot1dTpFdbPort
# ============================================================
# port-channel: CISCO-PAGP-MIB::pagpGroupIfIndex
# LACP portchannel: IEEE8023-LAG-MIB::dot3adAggPortSelectedAggID
# Linux: 
#  - bond0 配合 port-channel 一起使用；
#  - bond1 只能显示当前激活的那个端口，另外一个无法得到；
#  - bond4 配合 LACP portchannel 一起使用；
#  - bond5/6 可以同时看到所有连接的端口；
# ============================================================

cd -- "$(dirname -- "$0")" || exit

# set params
if [ "$1" == "-n" ]; then
	switchmap=1
	shift
fi
siwtchlist="${1:-switch.list}"
hostmacmap="${2:-host.mac}"
asamacmap="${3:-asa.mac}"
commuity=XXXXXX

# get MIB to associative arrays
mibarray() {
	[ -n "$3" ] && commuity="$commuity@$3"
	snmpbulkwalk -OX -OQ -v 2c -c "$commuity" $1 $2 2> /dev/null | grep -v '= No Such Instance' | sed -r "s/$2\[([^]]+)\].* = ([^ ]+)$/[\1]=\2/" | tr "\n" " "
}

# Main function
switch_host_map() {
	local switchip="$1"

	# hostname
	local switchname=$(snmpget -Ov -OQ -v 2c -c $commuity $switchip SNMPv2-MIB::sysName.0)
	[ -n "$switchname" ] || return 1

	# ifname <--> port
	eval local -A ifindex0ifname=( $(mibarray $switchip IF-MIB::ifName) )
	eval local -A ifport0ifindex=( $(mibarray $switchip BRIDGE-MIB::dot1dBasePortIfIndex) )

	# port-channel map
	eval local -A ifindex0ifindex4lacpportchannel=( $(mibarray $switchip IEEE8023-LAG-MIB::dot3adAggPortSelectedAggID) )
	eval local -A ifindex0ifindex4portchannel=( $(mibarray $switchip CISCO-PAGP-MIB::pagpGroupIfIndex) )

	# CDP Info
	eval local -A ifindex0cdpeviceid=( $(mibarray $switchip CISCO-CDP-MIB::cdpCacheDeviceId) )
	eval local -A ifindex0cdpeviceport=( $(mibarray $switchip CISCO-CDP-MIB::cdpCacheDevicePort) )

	# mac/ifport for every vlan
	local vlanlist=$(snmpbulkwalk -Oq -v 2c -c $commuity $switchip CISCO-VTP-MIB::vtpVlanState | awk -F'[. ]' '$(NF-1) < 1002 {print $(NF-1) }')
	local -A mac0ifport
	for vlan in $vlanlist; do
		eval mac0ifport+=( $(mibarray $switchip BRIDGE-MIB::dot1dTpFdbPort $vlan | tr : _) )
	done

	# ifport <---> (cdp|mac|hostname)
	echo -e "\n$switchname[$switchip]:"
	for ifindex in $( xargs -n 1 <<<"${!ifindex0ifname[@]}" | sort -n); do
		for ifport in ${!ifport0ifindex[@]}; do
			[[ ${ifport0ifindex[$ifport]} == $ifindex ]] && break
			unset ifport
		done
		ifname=${ifindex0ifname[$ifindex]}

		# cdp
		cdpeviceid=${ifindex0cdpeviceid[$ifindex]}
		cdpeviceport=${ifindex0cdpeviceport[$ifindex]}

		# mac
		maclist=""
		macnum=0
		for mac in ${!mac0ifport[@]}; do
			[[ ${mac0ifport[$mac]} == $ifport ]] && {
				maclist+="${mac//_/:}"$'\n'
				((macnum++))
			}
		done

		# portchannel
		local lacpportchannelifname=""
		lacpportchannelifindex=${ifindex0ifindex4lacpportchannel[$ifindex]}
		[ -n "$lacpportchannelifindex" ] && [ "$lacpportchannelifindex" != 0 ] && lacpportchannelifname=${ifindex0ifname[$lacpportchannelifindex]}
		portchannelifindex=${ifindex0ifindex4portchannel[$ifindex]}
		local portchannelifname=""
		[ -n "$portchannelifindex" ] && [ "$portchannelifindex" != "$ifindex" ] && [ "$portchannelifindex" != 0 ] &&
			portchannelifname=${ifindex0ifname[$portchannelifindex]}


		# interface info
		if [ -n "$cdpeviceid" ]; then
			echo -e "$ifname\t$cdpeviceid[$cdpeviceport]"
		elif [ $macnum -eq 1 -o $macnum -eq 2 ]; then
			host=$(
				for mac in $maclist; do
					grep -h -w $mac $hostmacmap $asamacmap | awk '{print $1}'
				done | sort -u)
			[ -z "$host" ] && host="<unknown>"
			echo -e "$ifname\t"$host
		elif [ $macnum -gt 1 ]; then
			echo -e "$ifname\t<floading>"
		elif [ -n "$portchannelifname" ]; then
			echo -e "$ifname\t[$portchannelifname]"
		elif [ -n "$lacpportchannelifname" ]; then
			echo -e "$ifname\t[$lacpportchannelifname(LACP)]"
		else
			:
			# echo -e "$ifname\t<down>"
		fi
	done | column -t | sed 's/^/\t/'
}

for switch in $(<$siwtchlist); do
	switch_host_map $switch
done