Unusual Issue with SR3120 Nortel

[CiscoWizard]

We are having an issue with our Nortel 3120 routers as of late. This wasn't something that happened back when I first started, which was over ten years ago. Lately, this issue happens frequently. What happens is, something prevents us from accessing our equipment remotely (with telnet or SSH) or through the console port. The only thing that clears this issue is doing a full reboot of the router. This normally isn't that big of a deal, but the system being controlled through this router is exceedingly important, so having to reboot it is always met with a long list of questions from upper management. They're not always easily willing to accept our solution.

What would cause this issue? Someone else I work with keeps mentioning a memory issue that eventually maxes out, but as I said earlier, this wasn't happening ten years ago. Is there a command or configuration that needs to be changed, or maybe a command that can be used to clear the memory buffers if that is indeed the issue. Below are the results of the "show version" command:

3120_West > show version
HW Assembly REV:                     A
PCB Assembly REV:                    A
MB FPGA Revision Number:             0x11
BOOT Device:                         FLASH
Downloadable FLASH Bootcode Version: r9.2
Physical EPROM Bootcode Version:     r9.1_062706
Software Version:                    r9.3.3

[Otanx]

Even 10 years ago that router was old. Considering how old that is I would assume it is just failing slowly. If it is really important then spend some money and replace it.

-Otanx

[CiscoWizard]

You've read my mind, my friend. If only management would be so quick to agree to that. They're so apprehensive that nothing will come back up once we connect the new equipment that they're refusing the upgrade. We even have a backup of the Nortel on standby in case the original fails to be reinstalled.

[Otanx]

If you swap in the spare does it have the same problem?

-Otanx

[CiscoWizard]

We've kept it connected in a lab environment, but we've yet to have that same problem. The configs appear to be matched so we weren't thinking it was a configuration issue. The age of the device seems to be the only explanation people have come up with, which I suppose is entirely possible. I've just been hoping it is something that can be solved to fix the current device. I'd still like to replace it with something newer, but it would still be nice to know it was something other than age. That's such a boring solution.   

[config t]

Wow. The Avaya sticker they put over the Nortel logo must have fallen off. 10-years ago Nortel Networks had already ceased to exist.

[CiscoWizard]

Then I probably shouldn't tell you about the Wellfleet and Bay Networks routers we have in our data center.

[icecream-guy]

Then I probably shouldn't tell you about the Wellfleet and Bay Networks routers we have in our data center.

Please do, my hacker friends are much interested in your network design and details.