Bundle 3 T1's using 2620

[s.waddell]

I know this thread my sound similar to others, but I haven't done anything like this before.

I have 3 point-to-point T1's going from my HQ to a branch office. I have 2 - 2620's with 3 WICS in them. What is the best way to aggregate the three T1's into a single pipe? I've read others regarding Frame-Relay etc, but this is a private point-to-point not sure if it makes any difference. Thanks for your help.

[Richard Burts]

If you have 3 T1s (not frame relay) and you really want to treat them as a single pipe, then what you need to do is to configure the serial interfaces for encapsulation ppp, and then to configure ppp multilink. This will take the 3 physical links and treat them as a single logical entity and split the traffic accross them.

If you do not really need a single logical entity then a somewhat simpler and lower overhead solution if to configure the three interfaces and run a routing protocol (EIGRP or OSPF, or perhaps even RIP) on them. The routing table will have 3 equal metric paths to the destinations reachable through the remote router and will load balance over the three interfaces. Using CEF you can even configure whether you want load balancing to be per destination or per packet.

[thisisshanky]

A sample ppp multilink config will look like this...

R1

int s0

no ip address

encap ppp

ppp multilink

ppp multilink group 1

int s1

no ip address

encap ppp

ppp multilink

ppp multilink group 1

int s2

no ip address

encap ppp

ppp multilink

ppp multilink group 1

int multilink 1

encap ppp

ppp multilink

ip add 10.1.1.1 255.255.255.0

R2

int s0

no ip address

encap ppp

ppp multilink

ppp multilink group 1

int s1

no ip address

encap ppp

ppp multilink

ppp multilink group 1

int s2

no ip address

encap ppp

ppp multilink

ppp multilink group 1

int multilink 1

encap ppp

ppp multilink

ip add 10.1.1.2 255.255.255.0

Use "show ppp multilink" to verify.