Force Speed/Duplex on Cisco 4331 w/out OOB access

[Jonnyballgame34]

Hi, 

I posted a similar question to this once before, and wasn't able to find a resolution, so I was hoping to give it another go as I still have the problem. 

I have a newly deployed 4331.  The Wan interface is set to auto negotiate, and I need to change it to 100 full.  The problem is I don't have any other connectivity to the router.  On other routers, I know if I do a 

Config int gi0/0

speed auto

duplex full

it will drop temporarily after the change then come back up.  however the default on these 4331 is "negotiation auto", (config below).  To change the interface, the first command is "no negotiation auto". The problem is that this will drop the interface, and it won't come back up.  I know because I tried it couple of times with delayed reloads.  The WAN interface is my only access.  Is there any workaround? 

Thanks very much, 

interface GigabitEthernet0/0/0
bandwidth 20000
no ip redirects
no ip unreachables
no ip proxy-arp
ip nat outside
load-interval 30
negotiation auto
no cdp enable
service-policy output SHAPE->20M
end

[Joseph W. Doherty]

Are you saying the after applying the "no negotiation auto" command, you lose access to device and a delayed reload doesn't restore access, or just you lose immediate access to the device, making it impossible to apply the next change, but the timed reload does restore access?

If the latter, what I've found works, you place the commands you need into a file, copy that file to flash, then issue one command to copy the flash file into the running config.  If done correctly, interface should drop and recover.  Additionally, a delayed reload can be used to restore prior configuration if the foregoing doesn't work.

[Jonnyballgame34]

Hi,

Thanks for looking at my question.  Sorry it wasn't clear, its' the first one.  I put in a "Reload in X", tried the non negotiate auto it didn't come back on it's own---it did return on the reload, (I set it up in case I lost access).

the flash fix sounds clever and promising, I'll give it a shot. 

[Jonnyballgame34]

how do I copy over the commands...patch them into a txt and then rename the extension .bak? 

[Joseph W. Doherty]

The way I do it, I set up the commands in a text file on my personal computer, then copy that file to the device's flash via tftp or FTP.

[Jonnyballgame34]

Hi--

You answered this question for me a couple of months ago.  I finally got an opportunity to use this method and it's been quick handy for me. Turns out the 4331 will eventually pick up again if you wait long enough, but you have to do mulitple steps and it's unreliable.  This is much better. thanks again

[Mark Malone]

Hi you dont have to use reload in x with ios-xe ---setup archive back config up to flash  and then use conf t revert time x

This will prevent router/switch reloading and still revert back config if you get kicked out  , saves you bouncing hardware continuously

[Joseph W. Doherty]

Great suggestion - but just wanted to also note, when I've manually used revert, I've sometimes encountered issues, but seems mostly a problem when there's a mass of involved changes.

[Dwyane Everts]

I realize this is a little old, but here's another way using TCL for anyone else that hits this issue:

reload in 0:05
tclsh

set fixinterface {
ios_config "interface gi0/0/2" "no negot auto" "speed 100" "duplex full"
}

eval $fixinterface

Once you regain access, "cancel reload" and "copy r s" (wr mem)