Cisco 1941 upgrading PTP interace from serial to gigabit ethernet

[Manuel Cruz]

We recently acquired a new PTP service upgrade (ethernet) . We are still using our old one PTP 1.5mb connection on our serial interface. I purchased and installed the new GB ethernet interface to compensate for the increase in bandwidth provided by the new PTP that was installed. The new EHWIC-1GE-SFP-CU is installed and configured with an an internal address to be used on both sides of the new PTP between my 2 Cisco 1941 Routers. I also included this new connection into EIGRP as well. I could use some help after my tesiting yesterday hasnt produced any help hints at what I'm missing in all of this configuration.

[chrihussey]

It's not clear what the problem is.

Is the link up and is there connectivity across it? Can either side ping each other? Are EIGRP neighbors established?

Please specify the issue and provide configs if possible.

Thanks

[Manuel Cruz]

Thankss for your response Chrihussey. I temporarily have the link down but i bring it up at the end of each day to work on it until i get it up and working fine. Its been a while since i came back to it so this is what I've done since then and what i think needs to be done. I already created EIGRP routes i just need to create the neighbor relationship between them like you mentioned with the ip summary-address command on both sides of PTP GB interfaces then turn them on so that they can connect up. I just forgot that the last time i worked on this i left it half completed before i shoul dhave tested it. Here is some interface info:

Network: 10.255.255.248 // 255.255.255.252 // 0.0.0.3

(My Side)

GE 0/1/0: 10.255.255.249  /30

(Other Side)

GE 0/1/0: 10.255.255.250 /30

I believe i just need to issue the command to both PTP sides of the GE interfaces create the neighbor relationship:

Configure Terminal

Interface GG 0/1/0

Config-if: ip summary-address eigrp 100 10.255.255.248 255.255.255.252

What do you think? I know i didnt give you the full print out that alot of users give but i'm happy to give you more info if needed. I deeply appreciate your expertise.

[Manuel Cruz]

 i think i got my commands mixed up to create the neigbor i need to do these commands on the both interfaces on there respetive sides, i believe this is it:

Router EIGRP 100

Network 10.255.255.248

neighbor 10.255.255.250 GG 0/1/0            MY SIDE to COLOCATION

 Router EIGRP 100

Network 10.255.255.248

neighbor 10.255.255.249 GG 0/1/0            COLOCATION to MY SIDE

[chrihussey]

To establish EIGRP neighbors you just need to make sure the network is in the EIGRP global config on both sides:

!

router eigrp 100

network 10.255.255.248 255.255.255.252

!

It should not be necessary to define the neighbors explicitly

Is that the information you need and does that work for you?

[Manuel Cruz]

Oh ok I just figured most people and books I've read recommended to reduce multicast/unicast traffic by keeping summarization disabled so you can utilize static neighbor configuration. By running those 2 commands would they interfere with my current serial interface's old PTP connection which has the connection info below:
OLD - Serial 0/0/0
Network: 10.255.255.252 // 255.255.255.252 // 0.0.0.3
MY SIDE: 10.255.255.253 /30
COLOCATION: 10.255.255.254 /30
Broadcast: 10.255.255.255

I can run you recommended command with the 2 new interface down and turn them on later and they should pair up as neighbors automatically?

[chrihussey]

Since this new PTP has better metrics it would be the preferred path compared to the other older serial connection.

You could however leave the new connection up and simply make the interfaces passive in EIGRP:

!

router eigrp 100

network 10.255.255.248 255.255.255.252

passive-interface g0/1/0

!

This way you could keep the new link up, establish CDP neighbors but EIGRP neighbors would not occur until you remove the passive-interface statement. You would now be able to ping across and monitor the new connection without actually passing traffic.

Hope this helps.

[Manuel Cruz]

Well I think your first command should do it. I'll start by disabling or unplugging the old serial interface cable. After I finish running the first command in global configuration mode on both sides of the PTP. I'll no shutdown the GB Int's to bring them up and then use a test VoIP Avaya phone to make sure traffic is flowing thru.
One last question and I'll mark your help as solution. Let's say I go thru with settings up the new PTP. I'd like to plan several steps ahead in case something happens. Will my old PTP still be useable if I have it up and the new one down? If something were to happen and I have to revert to using the old PTP can it still be useable if the new interfaces are fully configured but temporarily disabled? Well the router try to utilize the new PTP in some load balanced or road robin fashion despite it being shutdown? What I'm trying to say is that I want to proceed but in the spirit of handling production level equipment, I want to have a safe place to back step in case of a mishap leaves me with an unusable or a malconfigured setup for the new interface.

[Manuel Cruz]

Oh I forgot to add one last sentence to that latest reply. Can I configure the new interface while keeping it disabled and continuing to use the old interface until I'm ready for the implementation? I just basically want to do all of the ha s work before I get ready to swap it over in one fell swoop.

[chrihussey]

Basically, you should be able to bring up the new interface, have it in passive mode in EIGRP and enable it when you want to make it active. You can keep the older interface up the entire time. If you do a "show ip route" with the new interface up and with EIGRP neighbors established you should see it as the preferred route. If there is anything anomolous happening you could also passive the older serial route while the new is active.

Either way you would be in total control. You only have to passive one side as it will prevent EIGRP neighbors from forming.

[Manuel Cruz]

The new one takes priority because of the greater bandwidth and latency due to eigrp's ability to grade a wan's capability right?

[chrihussey]

Yes it should, provided the default interface bandwidth and delay settings have not been changed.

[Manuel Cruz]

chrihussey, it's been a while since we last communicated. I eventually got around to running the command to kick off the EIGRP for the new PTP pipe connection between my 2 1941 routers. So the connection shows up in EIGRP topology as successfully connected but they still don't show up as neighbors. The connection isn't joining up is what I'm getting to. I think I'm leaving out the EIGRP command line to neighbor them first. I did the network followed by the network address and mask as you mentioned but still no go, should i proceed to entering there neighbor info for each of the 2 sides? I  really appreciate your help.

I.E.

Router EIGRP 100

Network 10.255.255.248

neighbor 10.255.255.250 GG 0/1/0            MY SIDE to COLOCATION

 Router EIGRP 100

Network 10.255.255.248

neighbor 10.255.255.249 GG 0/1/0            COLOCATION to MY SIDE

[paul driver]

Hello

Using the neighbor command you are specifying unicast eigrp not multicast if that is the case you need the neighour command and the network command to accomplish this and also you cannot have two different adjacency either , they all need to be unicast or multicast.

Also when you do create the new adjacency ( unicast or muticast) why not just bring the new PTP link up to form an additional eigrp adjacency but on either side of the new  link apply a high delay value  , then eigrp will keep using the old path until you happy with the new one?

both side of the P2P link:

rtr1
int gig0/1
description new PTP link
delay 100000
ip address 10.255.255.250 255.255.255.248

router eigrp 100
neighbor 10.255.255249 GIG0/1<----for unicast adjacencys
network 10.255.255.250 0.0.0.0

rtr2

int gig0/1
description new PTP link
delay 100000
ip address 10.255.255.249 255.255.255.248

router eigrp 100
neighbor 10.255.255.250 GIG0/1  <----for unicast adjacencys
network 10.255.255.249 0.0.0.0

res
Paul

[Manuel Cruz]

Thanks Paul, I don't care at this point about bringing one up while keeping the other up. I just want to finally get the the new PTP up and working. So your saying without the delay all i need to do is finish off with what i said in my previous post? I thin you got the wrong interface in your post, its GE 0/1/0 not GE 0/1 unless you meant that intentionally?