Cisco 2514 Router - Lose IP Address when power goes out

[Bedrock1977]

I have a Cisco 2514 Router configured as my DSL Router. The External interface is set to receive an IP address via DHCP from AT&T automatically. However, when the power goes out and the modem shuts off, I lose that address and even though the modem gets a new one, the router interface does not update. Does anyone has suggestions on how I can fix this and is there any way I can keep this from happening again?

Thanks,
Bedrock1977

 

[North323]

get a static IP? sounds like the router boots before the dsl router. post a config of the router, we can take a gander.

 

[Bedrock1977]

Here is the configuration for the 2514 Router. It is an older router and takes a while to boot up. The modem finishing it's boot up process in no time.

Current configuration : 2015 bytes
!
version 12.3
service config
service timestamps debug datetime msec
service timestamps log datetime msec
no service password-encryption
!
hostname DSL_ROUTER
!
boot-start-marker
boot-end-marker
!
no aaa new-model
ip subnet-zero
no ip domain lookup
ip dhcp excluded-address 192.168.1.1
ip dhcp excluded-address 192.168.1.2
!
ip dhcp pool insideDHCP
network 192.168.1.0 255.255.255.0
default-router 192.168.1.1
dns-server 208.67.222.222 208.67.220.220
!
!
!
!
!
interface Ethernet0
description EXTERNAL ETHERNET INTERFACE TO THE INTERNET
ip address dhcp
ip nat outside
no ip route-cache
no ip mroute-cache
!
interface Ethernet1
description INTERNAL ETHERNET INTERFACE FOR PRIVATE CLIENTS
ip address 192.168.1.1 255.255.255.0
ip nat inside
no ip route-cache
no ip mroute-cache
!
interface Serial0
no ip address
encapsulation frame-relay
!
interface Serial0.102 point-to-point
ip address 10.1.1.1 255.255.255.0
frame-relay interface-dlci 102
!
interface Serial0.103 point-to-point
ip address 10.1.2.1 255.255.255.0
frame-relay interface-dlci 103
!
interface Serial0.104 point-to-point
ip address 10.1.3.1 255.255.255.0
frame-relay interface-dlci 104
!
interface Serial1
no ip address
shutdown
!
router eigrp 10
redistribute static
network 10.0.0.0
network 192.168.1.0
auto-summary
!
ip nat inside source list 1 interface Ethernet0 overload
ip nat inside source static tcp 192.168.1.3 3389 interface Ethernet0 3389
ip http server
ip classless
!
access-list 1 permit 192.168.1.0 0.0.0.255
access-list 1 permit 192.168.2.0 0.0.0.255
access-list 1 permit 192.168.3.0 0.0.0.255
access-list 1 permit 192.168.4.0 0.0.0.255
!
end

 

[Bedrock1977]

To add a little more information...the DSL modem is connected to Ethernet0 and the 2950 Switch is connected to Ethernet1.

 

[jeter]

You mention the dsl is losing power. What is the cause of this issue? Do you have a UPS? I also agree that a static ip for the dsl is used... You will need to bridge the dsl router and put the static ip on the Ethernet.


Go Army!
Tek-TIP Member 19,650

 

[Bedrock1977]

Well the dsl modem loses power when the power flickers on and off from a storm or just a typical brownout during the summer months. Do you feel that the static IP address would solve the issue?

What does bridging the router accomplish and how do you do it?

 

[itbycisco]

just a suggestion make your fa0/1 which is the 2900s switch to trunk port wiht dot1q and set the other side as well with VTP domain of server on the router. if didn't work try to bump the code (upgrade, may have some bug in the software).

 

[North323]

you can get a UPS for the dsl router. i think a static would resolve this...most likely cause is its getting a new IP and the old IP mac is still bound to the dsl and a clear arp is probably needed

 

[Bedrock1977]

For the time being, I reverted back to using the DLINK router for internet access until I can reconfigure the lab. I did purchase a Cisco Pix 501 Firewall and hope to incorporate that into the lab somehow. Thanks for everyone's input.

 

[CiscoGuy33]

Bedrock1977,

Like several have said - GET A UPS - $64 for APC UPS at Sam's.

Brownouts, spikes, power flickers, summer storms - they will ZAP that D-Link faster than anything :-(

I lost a D-Link and Linksys - then I got smart and got 2 APC UPS's so all my network equipment is on one (firewall, 2924 switch and 2651XM router) and my 2 main computers on the other - now when the power flickers (in Florida we get flickers all the time) I just keep on keepin on

Just a thought, I will say that the electric company dropped my neutral line once while working 1 house down - light bulbs got super bright and then blew, I lost $1,500 worth of TVs, phones etc. (what the electic co paid me) everything in the APC UPSs did not suffer any damage and the TVs were in some pretty good surge protectors!!

Once again - just a thought!

E.A. Broda
CCNA, CCDA, CCAI, Network +

 

[Bedrock1977]

Sure...well I appreciate the incite. I will definitely look into purchasing one or two of those. At that time, I needed to get the computer back on the internet ASAP so my wife could use it. Do you know the amount of time the $64 UPS will give you?

 

[North323]

maybe an hour...maybe more, depends what else you have plugged in to it

 

[CiscoGuy33]

Bedrock1977,

It comes with the "Powerchute" software from APC so once hooked up it will tell you exactly based on what is plugged in, but it is not alot from what I remember - 15-20 min enough so that you can shutdown if needed but not enough to sit out a long blackout.

My main use is those little electric glitches - I have an older neighborhood with lots of trees and critters that shortout things along the line, I am seldom without power for more than 30 seconds - normally it is just a quick up/down/up - just enough to reboot everything - IF I DID NOT HAVE A UPS!!!!!!

Worth every dime spent!

E.A. Broda
CCNA, CCDA, CCAI, Network +

 

[burtsbees]

Um, what dhcp address does the router get when it works? Is it by chance in the same subnet as addresses your router is trying to hand out?

/

 

[Bedrock1977]

Ok. Jeremy Cioara mentioned in one of his CBT Nuggets videos that he has a UPS that has a web interface to power on his entire rack remotely if he wants to access it. Something like that would be really neat to have but probably costs a pretty penny.

CiscoGuy33: I researched some of the cheaper UPS units, and I found they have a USB interface. Is that what your unit has?

burtbees: I have DSL with Dynamic addressing - so every time the modem shuts off, I get a new address. I assume it is in the same subnet as my internet network, 255.255.255.0.

 

[CiscoGuy33]

Bedrock1977,

YES - it has a USB - an older one that I have had a serial interface but the new ones all seem to be USB - I would make sure it is APC !!!!!

E.A. Broda
CCNA, CCDA, CCAI, Network +

 

[burtsbees]

I assume it is in the same subnet as my internet network, 255.255.255.0."

Hmmm...anyone wanna touch this one?lol

Bedrock---subnet, not mask...

The modem hands out an IP address to your router via dhcp. Your router hands out IP addresses to computers hooked to the switch via dhcp. These two dhcp pools---are THEY in the same network? Subnet=network. If so, well, you have a layer 3 switch with one LAN interface that can't route, basically...lol

By the way, modems a lot of times actually hand out addresses in the 192.168.0.0/16 range, not /24...that means 255.255.0.0, not 255.255.255.0

/

 

[Bedrock1977]

Yeah - I realized what I did there. Oops! I knew that. It has been a long day.

No, the two dhcp pools are not in the same network.