This article is all about how to configure PAGP (Port Aggregation Protocol) on Cisco switches. We all know that there are total three methods are present to configure EtherChannel in Cisco switches. That is static, PAgP and LACP. In the previous tutorial, we configure EtherChannel on switches using the static method. Now in this tutorial, we use PAgP method to configure EtherChannel on Cisco switches.
What is PAgP?
Port Aggregation Protocol (PAgP) is a cisco system proprietary networking protocol, which is used for automated, logical aggregation of Ethernet switch ports, known as EtherChannel. The PAgP is proprietary to Cisco Systems. A limitation of port aggregation protocol is that all the physical ports in the aggregation group must reside on the same switch. The Advantage of port aggregation protocol is “The line speed of a PAgP port is the total of line speeds of each its physical ports”. So, let’s start here how to configure PAgP on Cisco switches.
Now to understand this whole process we take a lab in cisco packet tracer. In this lab, we take two switches and four pcs.
We do this whole lab in two parts. In the first part, we configure PAgP protocol on Cisco switches and also assign an IP address to all the PCs. After that in the second part, we run troubleshooting command on switches and troubleshoot our PAgP configuration on switches.
Now, first of all, we configure PAgP on both the switches using given below command
For switch S1
Switch>enable Switch#config terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)#hostname S1 S1(config)#int range fa0/1-2 S1(config-if-range)#channel-group 1 mode desirable S1(config-if-range)# Creating a port-channel interface Port-channel 1 %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to down %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to down %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to up S1(config-if-range)#exit
For switch S2
Switch>enable Switch#configure terminal Enter configuration commands, one per line. End with CNTL/Z. Switch(config)#hostname S2 S2(config)#int range fa0/1-2 S2(config-if-range)#channel-group 1 mode desirable S2(config-if-range)# Creating a port-channel interface Port-channel 1 %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to down %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/1, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to down %LINEPROTO-5-UPDOWN: Line protocol on Interface FastEthernet0/2, changed state to up %LINK-5-CHANGED: Interface Port-channel 1, changed state to up %LINEPROTO-5-UPDOWN: Line protocol on Interface Port-channel 1, changed state to up S2(config-if-range)#exit
After that now assign IP address on all the PCs according to your need and use ping command to check whether they are communicating with each other or not
Now in the second part, we run troubleshooting command on one of the switch and verify our configuration on the switches. Like here we run troubleshooting command on switch S2 as the given below.
S2#show etherchannel summary Flags: D - down P - in port-channel I - stand-alone s - suspended H - Hot-standby (LACP only) R - Layer3 S - Layer2 U - in use f - failed to allocate aggregator u - unsuitable for bundling w - waiting to be aggregated d - default port Number of channel-groups in use: 1 Number of aggregators: 1 Group Port-channel Protocol Ports ------+-------------+-----------+---------------------------------------------- 1 Po1(SU) PAgP Fa0/1(P) Fa0/2(P) S2#show etherchannel load-balance EtherChannel Load-Balancing Operational State (src-mac): Non-IP: Source MAC address IPv4: Source MAC address IPv6: Source MAC address
THAT’S IT
By using above steps we can able to configure EtherChannel on Cisco switches. If you have any queries regarding this feel free to ask through the comment section and also provide feedback to us because your feedback is valuable for us.
