Ever wondered what Cisco PfR (Performance Routing) can do for you ?
Okie... No Issues.. Lets talk about it today...
First of all - What is PfR ?
During this series we will use these phases to explain how PfR works.
In this first article we will define all the steps necessary for getting PfR to work and set-up the necessary components and define interfaces.
The topology shows that we have 3 connections to our branch office (R9), 2 are transparent links, we don’t know how or what kind of Service Provider equipment is in the path and we have a third connection, trough an ISP with PPP connections were we are sure that it’s only 1 SP network.
PfR is designed to have 1 device that manages the entire setup; this includes pushing IGP or BGP information into the network and informing the other routers what to do. This router is called the Master Controller and this is the single location where you configure the policies after which they are pushed to the other routers.
The other routers that carry uplinks to the SP networks are called Border Routers. These devices are very easy to setup, as they only need information on where the MC is located. It’s possible to combine these roles in one device, which could be useful in smaller networks.
First we configure all necessary connectivity configurations and do a quick check if our layer 2 is working.
R2(config-if)#do ping 100.1.124.1 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 100.1.124.1, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/4/16 ms
R2(config-if)#do ping 100.1.124.4 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 100.1.124.4, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/4 ms
R2(config-if)#do ping 100.1.29.9 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 100.1.29.9, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/1/4 ms
R2(config-if)#do ping 100.1.26.6 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 100.1.26.6, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 16/17/20 ms R2(config-if)#
R2(config-if)#do sh ip int brie | ex unas Interface IP-Address OK? Method Status Protocol Serial0/1/0.1 100.1.26.2 YES manual up up FastEthernet1/0 100.1.124.2 YES manual up up FastEthernet1/1 100.1.29.2 YES manual up up
R6(config-subif)#do sh ip int brie | ex unas Interface IP-Address OK? Method Status Protocol Serial0/1/0.1 100.1.26.6 YES manual up up Multilink1 100.1.69.6 YES manual up up
R6(config-subif)#do ping 100.1.69.9 Type escape sequence to abort. Sending 5, 100-byte ICMP Echos to 100.1.69.9, timeout is 2 seconds: !!!!! Success rate is 100 percent (5/5), round-trip min/avg/max = 1/2/4 ms
R6(config-subif)#do sh ip route con 100.0.0.0/8 is variably subnetted, 3 subnets, 2 masks C 100.1.69.0/24 is directly connected, Multilink1 C 100.1.69.9/32 is directly connected, Multilink1 C 100.1.26.0/24 is directly connected, Serial0/1/0.1 R6(config-subif)#
Next we configure the ‘border routers‘, we start with these, as the configuration is very easy. To ensure no rogue devices will screw up our PfR setup, it’s possible to configure authentication. We connect over the loopback addresses and therefore it’s necessary to specify the interface were we want to source the communication from.
R2 & R4 ! key chain OER_AUTH key 1 key-string IPEXPERT ! oer border local Loopback0 master 100.1.1.1 key-chain OER_AUTH
R4(config)#do sh oer border OER BR 100.1.4.4 ACTIVE, MC 100.1.1.1 UP/DOWN: DOWN Conn Status: CONNECT FAILED OER Netflow Status: ENABLED, PORT: 3949 Version: 2.2 MC Version: 0.0 Exits
As you can see, not really intelligent stuff on the border routers, really everything is controlled from the master. When the session to the master is not ‘up’ yet, the border doesn’t know anything. Not even which interfaces are participating.
Last is to configure the ‘master controller‘.
Besides configuring the borders in this network, you also need to specify which interfaces are used for communication with the SP and which are for internal use. These are interface names on the border routers and not on the master.
R1 ! key chain OER_AUTH key 1 key-string IPEXPERT ! oer master logging ! border 100.1.2.2 key-chain OER_AUTH interface FastEthernet1/0 internal interface FastEthernet1/1 external interface Serial0/1/0.1 external ! border 100.1.4.4 key-chain OER_AUTH interface FastEthernet0/0 internal interface FastEthernet0/1 external
After configuring the master we see the neighbor sessions coming up, to see this information it’s necessary to enable ‘logging’ under the OER process.
*Sep 6 13:01:26.113: %OER_MC-5-NOTICE: BR 100.1.2.2 UP *Sep 6 13:01:26.125: %OER_MC-5-NOTICE: BR 100.1.2.2 IF Se0/1/0.1 UP *Sep 6 13:01:26.165: %OER_MC-5-NOTICE: BR 100.1.2.2 IF Fa1/1 UP *Sep 6 13:01:26.165: %OER_MC-5-NOTICE: BR 100.1.2.2 IF Fa1/0 UP *Sep 6 13:01:26.165: %OER_MC-5-NOTICE: BR 100.1.2.2 Active *Sep 6 13:01:26.165: %OER_MC-5-NOTICE: MC Active *Sep 6 13:01:26.213: %OER_MC-5-NOTICE: BR 100.1.4.4 UP *Sep 6 13:01:26.229: %OER_MC-5-NOTICE: BR 100.1.4.4 IF Fa0/1 UP *Sep 6 13:01:26.257: %OER_MC-5-NOTICE: BR 100.1.4.4 IF Fa0/0 UP *Sep 6 13:01:26.257: %OER_MC-5-NOTICE: BR 100.1.4.4 Active
R1#sh oer master bord det Border Status UP/DOWN AuthFail Version 100.1.4.4 ACTIVE UP 00:01:00 0 2.2 Fa0/1 EXTERNAL UP Fa0/0 INTERNAL UP External Capacity Max BW BW Used Load Status Exit Id Interface (kbps) (kbps) (kbps) (%) --------- -------- ------ ------- ------- ------ ------ Fa0/1 Tx 100000 75000 0 0 UP 6 Rx 100000 0 0 -------------------------------------------------------------------------------- Border Status UP/DOWN AuthFail Version 100.1.2.2 ACTIVE UP 00:01:00 0 2.2 Se0/1/0.1 EXTERNAL UP Fa1/1 EXTERNAL UP Fa1/0 INTERNAL UP External Capacity Max BW BW Used Load Status Exit Id Interface (kbps) (kbps) (kbps) (%) --------- -------- ------ ------- ------- ------ ------ Se0/1/0.1 Tx 1544 1158 0 0 UP 5 Rx 1544 0 0 Fa1/1 Tx 100000 75000 0 0 UP 4 Rx 100000 0 0
The master controller knows about the interfaces, their role and even capacity on how much bandwidth is available and currently used (depended on how timers are set).
R2(config-router)#do sh oer border OER BR 100.1.2.2 ACTIVE, MC 100.1.1.1 UP/DOWN: UP 00:13:55, Auth Failures: 0 Conn Status: SUCCESS OER Netflow Status: ENABLED, PORT: 3949 Version: 2.2 MC Version: 2.2 Exits Se0/1/0.1 EXTERNAL Fa1/0 INTERNAL Fa1/1 EXTERNAL R2(config-router)# PL-Pod123#4 [Resuming connection 4 to r4 ... ] *Sep 6
R4(config-router)#do sh oer border OER BR 100.1.4.4 ACTIVE, MC 100.1.1.1 UP/DOWN: UP 00:04:37, Auth Failures: 0 Conn Status: SUCCESS OER Netflow Status: ENABLED, PORT: 3949 Version: 2.2 MC Version: 2.2 Exits Fa0/0 INTERNAL Fa0/1 EXTERNAL R4(config-router)#
Now the master has been configured, the border routers know which interfaces they should monitor and NetFlow is automatically enabled to share the utilization status with the master controller.
Now the PfR setup is done we can start with the cool stuff. In the next part the profile phase will commence.
Now what ??? okie... try your hands on it... if you come across any issue lemme know... if you are stucked ( I am always up for a teamviewer session - Atleast for those who can contact me via phone)
Happy Config !!!