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Updating IOS in a Cisco 2500 router over FrameRelay

I was in the process of updating IOS in 46 different Cisco 2500 series routers over FrameRelay and encountered the following problem in two of the routers.

1. I first set the default route in the remote router to the frame relay ip address of the local router.

2. I changed the config-register to 0x2101 in the remote router and issues a reload command.

After reloading the router I was unable to telnet to the remote router to issue the copy tftp flash command. I check the local frame relay interface and it appeared to be up. But it would not respond to a ping. I dialed into the remote router and the frame relay interface appeared to be up. It would not respond to a ping nore could I ping across the frame relay circuit.

I changed the config-register back to 0x2102 and reloaded the router. The router came back up with all functions working.


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Re: Updating IOS in a Cisco 2500 router over FrameRelay

I used the following url for reference and upgrade a dozen of our 2500 series routers without any problem.


Re: Updating IOS in a Cisco 2500 router over FrameRelay

Were the DLCIs active and were you getting LMI? Did your telco have the LMI type set to auto detect? I won't mention any names, but Sprint is notorious for changing their LMI type on their customers.

If everything is ok on the telco end but you're not getting LMI or the line protocol isn't up then the last thing to check is if your boot ROM or image supports frame relay. Only recent versions of the 2500 boot ROM support frame relay. I know 11.0 and later supports frame relay. Show ver from the boot ROM IOS prompt will tell you what version you have. During an IOS upgrade process, the 2500 series is running its boot ROM IOS, not the IOS image in flash since it's over writing it. The only exception to this rule is if you have multiple partition on your flash.

Before doing any remote upgrade, make sure that your boot ROM or boot image (if you're using an older 4000 or 7500 series) supports your line cards or modules in the router being upgraded and the L1 and L2 WAN protocols being used over that WAN link. If not you may be in for some driving to do the upgrade on site or boot the router back to its original IOS.

Re: Updating IOS in a Cisco 2500 router over FrameRelay

2500s have a read only flash when they boot in normal mode. So the upgrade can be done only by rebooting it in Rxboot mode. In Rxboot mode, the router has minimal routing functions and hence probably the same reason why the router did not accept the telnet connection.

Probably a good alternative is to dial into the router using a modem and then do the upgrade in Rxboot mode.

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