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What is the longest running item of Cisco equipment in your data center? Can you beat 13 years?!

June 18, 2012 - 2 Comments

Where were you in 1998? Somewhere in one of our customers, a customer booted one of our 3640 routers, and it’s been running ever since without a reboot!

It’s been running since last century! Wow.   It’s been running since around the time my daughter was born, and a good few years before my son was born!  It’s been running longer that some of our competitors have been in existence, and longer than Juniper Networks has been a publicly traded company!

I learned this from an email was passed around my office, that highlighted this remarkable evidence of reliability.  It made me wonder, in your data center, what is your longest running piece of Cisco data center equipment?

And it also reminded me of some of our best practices for network reliability, such as Cisco Smart Services, described in this short VoD:

So now for the evidence.  As you can see from the “show version” Cisco IOS output below ……

…..  this system has been up for 13 years 18 weeks 5 days at the time this information was captured.

R1#sh ver

Cisco Internetwork Operating System Software IOS ™ 3600 Software (C3640-AJS-M), Version 11.2(15a)P, P RELEASE SOFTWARE (fc1) Copyright 1986-1998 by cisco Systems, Inc.

Compiled Tue 25-Aug-98 04:16 by kpma

Image text-base: 0x600088E0, data-base: 0x60920000

ROM: System Bootstrap, Version 11.1(19)AA, EARLY DEPLOYMENT RELEASE SOFTWARE (fc1)

R1 uptime is 13 years, 18 weeks, 5 days, 21 hours, 52 minutes System restarted by reload at 13:38:08 UTC Wed Nov 18 1998 System image file is “flash:c3640ENTPLUSAPPN112-15a_P.bin”, booted via flash

By any counts, this is impressive.   One of the systems administrators I used to work with in my earlier days in Cisco took tremendous pride regarding how long he could keep a router or server up and running without a reboot, and I once noticed how he nursed a long a server to beat his previous records.  Talk about dedication! 🙂

Having said that, is this what we’d recommend broadly?  With an older router, before the days of In-Service Software Upgrade (ISSU) in many devices, we would recommend keeping up to date with Cisco IOS releases, which involves a reload.  You can obtain specific release recommendations via the  Cisco Data Center Optimization Service and Cisco Network Optimization Service (which you may know as NOS), where we help you understand which release and feature sets are most appropriate for your needs, and proactively plan for software release end-of-life schedules.  (You can read more about Cisco offerings such as the Cisco Data Center Optimization Service in my previous blogs).

Also, crucially, you should ensure that you are running supported software releases so that you can benefits from Cisco’s industry leading Technical Support services and the proactive fault detection and avoidance features of Cisco Smart Services.

Of course, with ISSU now more widely available, we’ll see many more data center network elements exceeding 13 years of uptime, so please do let me know what is your longest running item of Cisco data center equipment!


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  1. Stephen:

    Always a fun topic–I did one of these a couple of years ago with some interesting results–I would not be surprised if some of these systems are still up:


    • Great post Omar, and some excellent insight can be gleaned from the comments. As I assert in my post, it’s an interesting topic, and it could be challenging in some ever changing data center environments – however it’s not necessarily best practice.

      But as you say a fun topic to check in on every now and again!

      thanks for the additional details.