Root Basics of Rooting, Recovery, and custom ROMs

[spottedcatfish]

Hey all,

I am new to the Android scene, but as a natural tinkerer, I'm feeling the itch to go beyond the standard settings in Android and get into rooting. I'm following along with a lot of the developments here, but I often feel like I'm missing a lot of the background knowledge and vocabulary (what is recovery, how does one access it, what are all these different programs - nandroid, adb, etc.) to have a really strong grasp of what's going on here.

Now, if this were my computer, I'd just hop right in and start following along as best I can and mess things up along the way, no biggie, I have multiple computers and I'm competent to fix them.

I don't have a landline though, so I want to be a little more prepared before I accidentally brick my link to the outside world. Is there a good "tinkering with Android primer" out there that any of you would recommend?

Also, how easy is it to get back from whence I came on the Ally? I read the thread on unrooting, and I honestly didn't understand a lot of it, so I'm just looking for a "not gonna happen" or "it'll be easy when you finally understand."

Thanks much!

 

[Mitchell4500]

The best way to root IMO is to download the AllyRR tool. Theres a thread about it. IF you want to un-root I dont know, but I dont see no reason for un-rooting.

 

[cdsmith]

Spotted, I was in the same place initially as far as the customization scene goes; the Ally was my first Android phone, and I followed a lot of the details, but was missing the big picture. I feel like I've figured it out now, so I'll try to give the high-level picture.

1. Rooting. This is just modifying the phone to give applications the ability to claim "superuser" privileges, which allows them to do anything. Once you get root (i.e., superuser) access once, "back doors" can be installed that allow applications to obtain it again. So the original root process posted here used a program called asroot2 (a hackish thing that exploits a security flaw in the older version of Linux used by Ally) to get root access the first time, and then installed su and Superuser.apk as the "back door" to let other apps do it.

2. Recovery. This is something that can be run outside of the Android operating system, which you can use to manipulate your system at a lower level than Android. It's sort of like BIOS in that way: it can be used regardless of the OS on the phone. Ally came with a locked-down recovery that wouldn't let us do anything, so someone posted a more open one you can write over the recovery partition on the phone to let you do more (such as flash new system images and back up and restore, and the like.)

Some confusion pops up here if you're reading about rooting and recovery on other phones. Some OTHER phones necessarily combine these two steps, because the only known way to get root is to first get an open recovery, and then flash a new system image including the back doors for root. So other sources will often say that certain things are true of rooted phones, when what they really mean is that they are true of phones that have replaced the recovery partition.

3. Custom ROMs. This refers to entirely new versions of the Android system software. Currently there are no significantly different custom ROMs that run on the Android; this is the next logical step. The Android operating system is open source, but certain components like drivers for the cell phone radio are specific to the model of phone, so are not included in Google's distribution of Android. We also have the source code to LG's Linux kernel now, and that should include those components. There's still a lot of integration work to be done, though, before a custom ROM can be built from scratch.

There are, on the other hand, ROMs floating around that people have built by modifying LG's default install, and then saving off an image of their modified phones. These are almost entirely stock ROMs, with just a few small changes (deleted apps, root, maybe a few utilities, etc.)

As far as bricking the phone, I'd feel fairly confident in the rooting and custom recovery steps. At least, I was comfortable enough to do them, and I'm not taking chances with my phone. They work fine. Custom ROMs have *vastly* more chances to brick your phone... on the other hand, because the custom recovery we've got going does Nandroid backups, this shouldn't be a big issue... just get a Nandroid backup before flashing anything over the default ROM, and you can restore the backup from the recovery menu should anything happen to the system imagine that prevents the phone from booting.