Is Rooting "Permanent"?

[Leonne]

I just rooted my Samsung Galaxy SII with an insecure kernel.
I'm doing all this because I want to install CyanogenMod. My question is, is this Rooting method permanent? Before I install CyanogenMod, I want to have my phone clean - That is, I want to restore it to factory settings cleaning up absolutely all my apps and all (y'know, like formatting) - Will that kill the rooting I just did?

 

[valorian]

When it comes to rooting each phone is different. I cannot say for the SGS2 but for the Incredible 2 there is a method to undo the root. You may want to ask this question in the SGS2 section.

Loading CM7 will not remove your root. As part of loading a new ROM like CM7 you will be clearing all cache and doing a factory reset prier to installing the ROM. This will give you a clean phone.

 

[nyydynasty]

return to stock:
[Heimdall][Odin][Stock][Root]UCKH7 Return/Unbrick to Stock (or Root) - xda-developers

it is not permanent.

 

[Leonne]

Thanks both!
I don't need to unroot at the moment but it's helpful to have that.
I will continue with the installation of CW7 now that everything's clear.

Thanks again!

 

[Frisco]

I don't need to unroot at the moment but it's helpful to have that.

It sure is helpful to have that. I don't root a new device until I've seen the unroot and sbf methods and files listed somewhere.

There are a few other angles to it, though.

We've seen many Android devices root exploited, then a leak of an OTA update will show up for rooters only, so having it rooted can be good if you're the type who wants to play with the OTA prior to its official release. But if you're like me, you'll want to unroot so your device will capture the official update instead of just being forcibly unrooted by the update, which seems to be happening more and more lately.

 

[Yeahha]

To add to what Frisco said, depending on your device most custom roms will prevent you from getting an OTA. Also many device will fail to update OTA or worse (soft brick) if you have done things like removed or frozen bloatware or are running a custom recovery.

If you are going to try to accept an OTA I suggest keeping an eye out on your device specific forums to see when it is coming and the root forum to see what you may need to do to either unroot or at least make the device safe and capable of accepting the OTA.