Why lose a router settings after a power outage?

[yesenia-m]

Hi Team

After a power outage lost my router configuration, was saved, reload the configuration, save, reboot and no problem.

How to know if my router is properly, all my services run smoothly? Why it happens that configuration is lost?

Are there any benefits the settings saved in flash?

Thank you

Regards

[Alessio Andreoli]

Hi Yesenia,

you should check the value of your register with:

show version

it should be on most of the routers 0x2102

Hope this helps

Alessio

[yesenia-m]

Hi Alessio

I have reviewed the register value, which is 0x2102.

My question is why this happens, because the configuration is lost after a power outage

Thank you

[Ivan Shirshin · Accepted solution]

Hi Yesenia,

Did you check if the NVRAM was empty or running config was empty?

If router booted with empty running config, it could be that startup got erased (NVRAM issue) or that it did not load it from startup to running (likely config-reg) issue.

Since in your case config-register ix 0x2102 and was not changed, the problem should be with NVRAM.

From me exprience, I have seen that in the following cases:

- config was not saved to NVRAM;

- at the time of powerdown the NVRAM startup file was accessed for editing (e.g. saving running config) and got corrupted or erased;

- NVRAM HW issues cause file system problems.

Is it reproducible in your case? E.g. if you powercycle the switch, do you see the same problem with config loss? If yes, check the NVRAM content.  That could give some hints.

Kind Regards,
Ivan Shirshin

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[Ivan Shirshin]

By the way, which switch/router model is that? Data in NVRAM (startup-config) is in some models powered by a battery, which could be getting weak.

Kind Regards,

Ivan Shirshin

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[yesenia-m]

Hi Ivan

     Its a router model 3825, (C3825-IPVOICEK9-M),

     To verify NVRAN (startup-config) if I see computer settings

     How I can know if it has a battery and this battery is low?

Thank you

[Ivan Shirshin]

Hi,

As far as I am aware, it has flash memory as NVRAM which does not require battery.

Lithium battery on this platform is used for real time clock only.

Kind Regards,
Ivan Shirshin

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