Router os

[jonk34567]

how to back up router configuration and os ?

[Julio E. Moisa]

Hi

In order to backup the configuration and IOS you can use a TFTP, FTP or using USB. Now if you want to make a backup of the configuration only you can use Putty (configuring output lines - please check the picture) or a third party software like NCM-Solardwinds or also you can use Cisco ACS.

Hope it is useful

:-) 

[Leo Laohoo]

Backup the OS by downloading the IOS from the Cisco website.

[Joseph W. Doherty]

Leo's answer is good, but it assumes you have access to Cisco's IOS downloads for your device and/or Cisco still provides them. Julio's answer allows you to bypass Cisco to make an IOS backup.

If you have two (or more) like devices, running identical IOS images, you might consider any as an IOS backup for the other(s). (NB: even if they are not identical, depending on available flash space, you can store other device IOS images on them.)

BTW, depending on the device, you might have other options for copying files (IOS, config, etc.), such as using SCP or CF modules.

[Leo Laohoo]

---

@Joseph W. Doherty wrote:
Leo's answer is good, but it assumes you have access to Cisco's IOS downloads for your device and/or Cisco still provides them. 

---

I'm not really a big "fan"of downloading the IOS from another appliance because there is no assurance that the file downloaded isn't corrupt.  

If the operator don't know what he/she is doing, then this method is fraught with danger.

Take the case of IOS-XE in Install Mode.  I'd like to see someone "backup" the OS by downloading the files.  All it takes is one corrupt file to spell a difference between a successful boot or ROMmon.

[Joseph W. Doherty]

I've been doing it for years, without an issue, but that doesn't invalidate your point.

You might also use the verify command (if supported) to validate the image.

[Leo Laohoo]

---

@Joseph W. Doherty wrote:
You might also use the verify command (if supported) to validate the image.

---

Correct.  Without going to the Cisco website, how does an operator know the MD5 hash value. 

---

@Joseph W. Doherty wrote:
I've been doing it for years, without an issue, but that doesn't invalidate your point.

---

That's the point.  You know this because you've been-there-done-that and wrote-a-book about it.  Other people don't.  I'm not going to teach them the "shortcuts"until they are confident enough to know how to recover an appliance in ROMmon.  

Now about questions for school work (like this thread), I will discuss the correct method.

[Joseph W. Doherty]

"Without going to the Cisco website, how does an operator know the MD5 hash value."

Some of the later versions, I believe, have what the MD5 hash is supposed to be embedded in the file. I.e. such can self verify.

That does raise the question, can't you just change it too? Well, in theory possibly, but it practice, maybe not easily. You need to distinguish between someone tampering with an image and just insuring a copy is good. For the latter, a good verification is sufficient, for the former, getting the hash from the Cisco site would be the better approach.

[Leo Laohoo]

---

@Joseph W. Doherty wrote:
Some of the later versions, I believe, have what the MD5 hash is supposed to be embedded in the file. I.e. such can self verify.

---

I agree.  This is the new selling point for the 9K and their self-verifying OS.