Trying to save time, anyone have advice?

instant000

I was going through,and I was trying to set up BGP peerings for a lab.

Due to the nature of the task, it said to not use loopback addresses.

So, I decided that since I needed the peerings to match IPs, I would debug icmp, and ping the other IP, and use the source-dest pairings to match.

Then I decided, why don't I just do this:
sh ip int brief | e una
as well as "debug ip icmp"across all participating in bgp
set up a tcl script to ping each ip once
in the debug, track the source-dest
Use the output to set my neighborships

Example:

Rack42R4#debug ip icmp
ICMP packet debugging is on
Rack42R4#tclsh
Rack42R4(tcl)#foreach address {
+>155.42.146.6
+>155.42.7.7
+>155.42.8.8
+>155.42.9.9
+>155.42.10.10
+>} {ping $address r 1
+>}

Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 155.42.146.6, timeout is 2 seconds:
!
Success rate is 100 percent (1/1), round-trip min/avg/max = 8/8/8 ms
Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 155.42.7.7, timeout is 2 seconds:
!
Success rate is 100 percent (1/1), round-trip min/avg/max = 16/16/16 ms
Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 155.42.8.8, timeout is 2 seconds:
!
Success rate is 100 percent (1/1), round-trip min/avg/max = 16/16/16 ms
Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 155.42.9.9, timeout is 2 seconds:
!
Success rate is 100 percent (1/1), round-trip min/avg/max = 16/16/16 ms
Type escape sequence to abort.
Sending 1, 100-byte ICMP Echos to 155.42.10.10, timeout is 2 seconds:
!
Success rate is 100 percent (1/1), round-trip min/avg/max = 12/12/12 ms
Rack42R4(tcl)#
*Mar  1 02:51:55.939: ICMP: echo reply rcvd, src 155.42.146.6, dst 155.42.146.4
*Mar  1 02:51:55.963: ICMP: echo reply rcvd, src 155.42.7.7, dst 155.42.146.4
*Mar  1 02:51:55.999: ICMP: echo reply rcvd, src 155.42.8.8, dst 155.42.0.4
*Mar  1 02:51:56.019: ICMP: echo reply rcvd, src 155.42.9.9, dst 155.42.146.4
*Mar  1 02:51:56.059: ICMP: echo reply rcvd, src 155.42.10.10, dst 155.42.0.4
Rack42R4(tcl)#

The advantage here was that I set it up one time, and run it many times (across several devices), as a time saver.

The disadvantage is that I came up with this on my own (Maybe that's an advantage?).

I'd like to know if someone has a quicker method for collecting this same information, as some portions of the labs can be tedious (collecting IPs). [I know that I am close to memorizing their IPs at this point, but I feel that each time I need to approach the lab like I have not seen it before, so I do the collections each time through, even if I know the result .... I just want to make sure that I'm as speedy as possible about it.)

instant000

Also, I just realized that my method doesn't take load-balancing into account, so it won't even be reliable. So, hrm ... need another way.

instant000

Maybe the point of the exercise is so that we appreciate "update-source"? I'll find out soon, I hope.

EdTheLad

You also have to take into account when routers have multiple interfaces and hence multiple paths between each other, which physical int to choose.I've used traceroute and then checking the rib costs to pick the best path.

Routerronin

EdTheLad wrote: »

You also have to take into account when routers have multiple interfaces and hence multiple paths between each other, which physical int to choose.I've used traceroute and then checking the rib costs to pick the best path.

Perty good advice for someone who mostly hates networking.

instant000

Thanks for the comments.

Maybe I'll start a lab thread when I've a better handle on the technologies.