cancel
Showing results for 
Search instead for 
Did you mean: 
cancel
419
Views
0
Helpful
4
Replies

3 routers point to point serial connections

jazzman93612
Level 1
Level 1

I need to configure point to point serial connections on 3 routers. One is a 2811 and the other 2 are 2801's. The Point to point lines are in place and are terminated with Kentrox 656 CSU/DSU's at each location. I was thinking of using ppp authentication. A LAN will connect at each router also. What is the best way to assign ip addresses to the serial interfaces? I am new at this.

4 Replies 4

jarathbu
Level 1
Level 1

Hello,

If you use a /30 mask for the point to point connections you will use the least amount of IP address space. If this is in a lab environment you can pick any range - if this will connect to a production environment you will need to get valid IP's.

If your topology is like:

R1 serial 0 <----> serial 0 R2 serial 1 <---> s1 R3

Then you can do"

R1

int s0

ip address 192.168.1.1 255.255.255.252

R2

int s0

ip address 192.168.1.2 255.255.255.252

int s1

ip address 192.168.1.5 255.255.255.252

R3

int s2

ip address 192.168.1.6 255.255.255.252

Hope that helps.

Regards,

James

that doews help, thanks, however, one other question, the 2811 has 2 serial WAN interface cards but shows 3 serial interfaces: s0/0/0, s0/1/0, and s0/2/0, is the s0/0/0 a logical interfaces and if so, what is it used for?

Hello,

Can you upload the output from a show diag from the 2811? Thanks.

Regards,

James

Just wanted to add a note.

If you are also connecting LAN's to the routers and obviously using a different subnet like a prefix of /24. Make sure you are running a Routing protocol that supports VLSM so you can use different subnets to save address space. That way you are not locked into on mask throught the entire network.

Hope this helps and please rate!!

Scott

Getting Started

Find answers to your questions by entering keywords or phrases in the Search bar above. New here? Use these resources to familiarize yourself with the community: