Here’s a handy list of ACL entries to allow your devices to speak routing protocols, availability protocols, and some other stuff. We’ll assume you have ACL 101 applied to your Ethernet inbound; your Ethernet has an IP of 192.168.0.1. BGP : Runs on TCP/179 between the neighbors access-list 101 permit tcp any host 192.168.0.1 eq […]
I use Google Analytics to track the 2 or 3 hits I get a day, and sometimes I see some interesting search terms. Yesterday, some googled up the term “does the ASA 5505 run HSRP”; I think that deserves a short article. The ASA and PIX firewalls don’t actually run any of the usual HA […]
Believe it or not, I got a request for an article on how to configure GLBP. I’m as shocked as you are, so here it goes. The Gateway Load Balancing Protocol (GLBP) is another Cisco-proprietary protocol for providing highly-available gateways on a network…but there’s a twist. GLBP, as you can figure out from the name, […]
HSRP (Hot Standby Router Protocol) is a Cisco-proprietary method for supplying a highly-available gateway for hosts to use. GLBP (Gateway Load Balancing Protocol) does the same thing. So, what’s the difference? HSRP works on layer 3 and provides a standby IP address for hosts on that network to use as their gateway (or other routers […]