Database Develop

Confusions about rooting and rom flashing

I've been doing a lot of reading and searching but still can't find a definite answer...
My understanding is that I need to root the device to flash a custom rom
But from the instructions for noobs, they don't usually specify that I have to root
I assume that rooting is a pre-requisite for everything...but then some roms advertise that they are rooted (for example, LeoFroYo)
So it the rooting process tied to the rom itself and I have to root everytime I flash a new rom (if the rom is not rooted)? Or is it universal like HSPL on WinMo?

Rooting is per rom. What is required to flash a custom rom is having an unlocked bootloader and a custom recovery image. From there you can flash a pre-rooted rom.
The root instructions assume that you're gonna keep using the stock version with root abilities added on top. Whereas if you're using flashing something like CM, that already has root and OS tweaks.

FaJu said:
Rooting is per rom. What is required to flash a custom rom is having an unlocked bootloader and a custom recovery image. From there you can flash a pre-rooted rom.
The root instructions assume that you're gonna keep using the stock version with root abilities added on top. Whereas if you're using flashing something like CM, that already has root and OS tweaks.
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Thanks! So does that mean when I get my phone out of the box, I have to root it once over the stock rom before I can flash any custom rom?

You need to root the phone originally and flash a custom rom. The "pre-rooted" means the rom is rooted. So if you flash that rom then you wont lose root. If you flash an un-rooted rom then you will lose it. So go through the steps and unlock your bootloader then flash a custom recovery image. Then decide which rom you wanted and flash it. All the custom roms are rooted.

futango said:
You need to root the phone originally and flash a custom rom. The "pre-rooted" means the rom is rooted. So if you flash that rom then you wont lose root. If you flash an un-rooted rom then you will lose it. So go through the steps and unlock your bootloader then flash a custom recovery image. Then decide which rom you wanted and flash it. All the custom roms are rooted.
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That explains it. Thanks for your answer

one more question:
I take it as when bootloader is unlocked, there's no way to lock it again? Not even flashing the stock boot image?

No, once you unlock the bootloader, it stays unlocked.

Just to be clear here you don't _have_ to "root your phone once"
On _most_ phones you need an exploit to be able to get to the bootloader, this exploit is often referred to as rooting. After the exploit you generally have superuser access until you reboot, on some phone this may allow you to get at the bootloader and write anything you want there (E.G. an OS that give you superuser access at boot time)
However the N1 lets you issue the command "fastboot oem unlock" that unlocks the bootloader, from there you can flash a recovery image that will allow you to flash the main OS without having access to Google's release signing keys. Hence you _could_:
1. Bootloader unlock
2. Flash Custom recovery
3. Flash Custom OS
Without ever actually having "root" access, it just happens that most Devs prefer having root access available in both recovery and any custom rom they cook up.

Question about Rooted phone without unlocking boot-loader

I asked this question in Android development forum but it was closed (without any comment, mad at Mods) here it is again, need pro's advice:
Recently I succeeded to root my phone with this great guide: http://forum.xda-developers.com/showthread.php?t=710842
(without cutting my battery )
Now I have two questions:
1. What should I avoid to keep my warranty? I now that I didn't unlock boot-loader so my warranty should be OK now, but what command exactly will unlock it and void my warranty? I know most people here assume that you unlocked boot-loader and they even use these two terms "unlock boot-loader" and "root" with the same meaning. Specifically does this command unlock boot-loader or void warranty? "adb root"
2. What should I avoid so I keep my root access? I know that if I flash the stock OTA FRF91 it will remove this root access, or if I flash an stock radio?! What would exactly force me to do the guide again to root the phone?

far as i know from G1 days flashing radio updates will not loose root, but flashing a ota update or "stock rom" over any will wipe and put you back from start with no root access, long as its a custom ROM you should be ok to flash away..
I too is on stock FRF91, with you root acess only and kinda want to keep it that way.. i may flash amon ra recovery img and go to enomther ROM, as thats closes to stock as possible..

bohlool said:
1. What should I avoid to keep my warranty? I now that I didn't unlock boot-loader so my warranty should be OK now, but what command exactly will unlock it and void my warranty? I know most people here assume that you unlocked boot-loader and they even use these two terms "unlock boot-loader" and "root" with the same meaning. Specifically does this command unlock boot-loader or void warranty? "adb root"
Click to expand...
Click to collapse
You only lose your warranty if you unlock your bootloader (specifically using the command fastboot oem unlock). Unlocking the bootloader turns of the OEM security and allows flashing of test signed images. Root is an entirely different concept where software on the phone is allowed to run with elevated root user privileges. Unlocking the bootloader allow you to flash custom images with the fastboot command. Without unlocking (and with root access), you would need the flash_image binary to do the same. Note that Google can void your warranty if you have root or a custom ROM when you send it for service, so u'll have to flash the shipping ROM and/or OTAs prior to sending.
bohlool said:
2. What should I avoid so I keep my root access? I know that if I flash the stock OTA FRF91 it will remove this root access, or if I flash an stock radio?! What would exactly force me to do the guide again to root the phone?
Click to expand...
Click to collapse
Installing any OTA or shipping ROM from Google/HTC with remove root access. Also, installing a custom ROM without root binaries will also remove root access (this would rarely exist).

Another Question
Thanks for replies, so helpful.
Now my question is does OTA updates include recovery software? if I installed a custom recovery and install OTA, do I still have custom recovery? I can install SU again because I would stay with stock ROMS with root access.

bohlool said:
Thanks for replies, so helpful.
Now my question is does OTA updates include recovery software? if I installed a custom recovery and install OTA, do I still have custom recovery? I can install SU again because I would stay with stock ROMS with root access.
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Click to collapse
No. Your custom recovery is separate from the ROM.
As long as you have a custom recovery, you can NOT properly download/install/flash the OverTheAir update.

OTA
OrganizedFellow said:
No. Your custom recovery is separate from the ROM.
As long as you have a custom recovery, you can NOT properly download/install/flash the OverTheAir update.
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Why I cant install OTA update? it is a signed zip file and my custom recovery should be able to install it? What is special about this OTA?

bohlool said:
Why I cant install OTA update? it is a signed zip file and my custom recovery should be able to install it? What is special about this OTA?
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Click to collapse
Well, the official OTA are signed by Google/HTC and the signature checks in custom recoveries can only validate the test signatures... only the official recoveries can validate the OTA signatures...

how to install RA recovery without unlocking boot loader?

Read Nexus One Wiki, in section "Guides"/"Root", then in section "Recovery", instead of spamming multiple threads.

Jack_R1 said:
Read Nexus One Wiki, in section "Guides"/"Root", then in section "Recovery", instead of spamming multiple threads.
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I am sorry.

ROM Manager Won't Doesn't Work

I have an N1 that I unlocked and rooted and was running CM7 RC1 when I decided to try the stock Gingerbread. This switch went perfectly, but now I don't think I want to stay on the stock GB but I can't seem to get ROM Manager to boot into recovery to allow me to flash another ROM. Do I have to do something differently now? BTW, I do not have root on the 'new' GB.
Thanks.

Unless you flashed a pre-rooted version of Gingerbread, you will have lost root and your custom recovery...
If this is the case, you have two options:
1 - Flash a custom recovery through an unlocked bootloader.
2 - passimg back to an older version of Android and root again...
Sent from my Nexus One using XDA App

tsprks said:
BTW, I do not have root on the 'new' GB.
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Click to collapse
This is your problem. ROM Manager installs a custom recovery, but only when your phone is rooted. You need to re-root GB.

Can I ask them how people flash custom recoveries without having root? I see threads all over the place that say that you don't have to root your phone to run these custom ROM's.

tsprks said:
Can I ask them how people flash custom recoveries without having root? I see threads all over the place that say that you don't have to root your phone to run these custom ROM's.
Click to expand...
Click to collapse
You have to root, but you don't have to unlock your bootloader.

You have to do one of the things:
1) Root.
2) Unlock the bootloader.
Rooting allows you to bypass security mechanisms from within the OS, and flash the custom recovery from there.
Unlocking the bootloader turns off the security mechanisms, and you can flash whatever you want directly from bootloader.
Both achieve the same thing, but in different ways.
Root privileges in OS are lost upon official upgrades.
Unlocked bootloader is never lost.
Unlocked bootloader allows for an easy way to gain root in the first place, regardless of the ROM.

How does an unlocked bootloader allow me to flash whatever ROM I want? ROM Manager won't run without root? Am I missing something? I've read the wiki's and threads about rooting an N1 and they all just seem to stop at unlocking the bootloader, well, my bootloader is unlocked but I can't get it to boot into CWM so that I can select another ROM. Is there another way to do this?

ROM Manager is only one, and not the most successful nor most powerful, way to flash ROMs or recovery. ROM Manager was made for non-understanding people to make the process look and feel easier. The most powerful way is directly from bootloader - which needs to be unlocked to allow it.
If you read all the threads, you'll see that unlocking the bootloader is just a first step - you can look carefully at "installing custom ROM" guide in Wiki. Or, for example, here:
http://forum.xda-developers.com/showthread.php?t=636795
Read the Wiki, look for recovery installation instructions using unlocked bootloader, execute. I suggest Amon_Ra's.

[Q] can you install clockworkmod after updating to 2.3.4?

i had a nexus one and was able to unlock the bootloader but i think i updated it to 2.3.4 and then tried to install CWM, which didn't work. i then discovered the antenna was not working correctly so i had to exchange the phone for another new one. once i get my new nexus one i was still thinking about installing CM7 and i just want to get some things straight about 2.3.4 and installing clockworkmod recovery.
will i be able to install CWM after i update my nexus one to stock 2.3.4? if not what is the highest stock build i would be able to do it with?
concerning the radio, if it is not possible to update to 2.3.4 and then install CWM i guess i'd have to update the radio by itself right?

You can unlock the bootloader and install cwm, or you can revert to an earlier version of Android, root, and then install cwm...

so i guess it's not possible to root and install CWM on 2.3.4? what's the latest version of android i would have to revert to for rooting and installing CWM?

There is no exploit for 2.3.4, so there is no easy root...
To downgrade, you have to do the passimg with a shipped image, and the most recent is FRG33. However, once rooted you can update all the way to 2.3.4 and keep root, if you do things in the right order...
You could also update to 2.3.3 and root and update to 2.3.4 keeping root - but the end result is the same...

You can also root 2.3.4 after unlocking the bootloader and flashing a custom recovery. From there, you would need to flash one of the su.zip files floating around (you may need a specific one for Gingerbread), which should remove the stock recovery checks (what replaces the custom recovery when you boot a stock install) and should add the necessary files for root access.

the first nexus one i received was on 2.2.1 so i guess if i plan on installing CM7 i should just keep in there and not bother upgrading anything (maybe the radio only)? just want to make sure where i stand so someone could help me accomplish these things. i know how to unlock the bootloader and i think i'll be fine installing CWM so what order should i:
unlock the bootloader
upgrade the radio (i guess i don't have to do this if i upgrade to 2.3.4)
install CWM
root
upgrade to 2.3.4
install CM7
i'm just making sure i know what i'm doing before i get my replacement nexus one and while i have attempted searching for answers i haven't been able to find the specific order or answer to my question. if anyone can correct any mistakes or assumptions i've been making please let me know.

If you are unlocking the bootloader, there is no need to root the current android install. The whole point of rooting the phone is so you can get the custom recovery on there so you can load CM on the phone. Since you are unlocking the bootloader, you can load the custom recovery using fastboot, then boot into it, wipe the phone and flash CM (and gapps).
And if it is a replacement, it will most likely be running the 5.08 radio, which seems to be the best one for Gingerbread.
So it would be:
Unlock bootloader
flash clockworkmod
boot clockworkmod (select the bootloader screen and then recovery, don't reboot)
wipe phone
flash CM and gapps
reboot
????
profit

DarkKnight62 said:
unlock the bootloader
upgrade the radio (i guess i don't have to do this if i upgrade to 2.3.4)
install CWM
root
upgrade to 2.3.4
install CM7
Click to expand...
Click to collapse
You don't need to upgrade to 2.3.4 unless you want to upgrade the radio and hboot. Of course, you can upgrade them without updating the OS, though upgrading them with OS will be safer.

ok, now that i know that installing CM7 will root my phone if i do it by unlocking the bootloader and installing CWM i am wondering if my phone will be rooted once i restore my nandroid backup that i will make (of stock 2.3.4 android) right before i install CM7?

No. Root is separate from unlocking your bootloader and whatever recovery you are running. Root is at the OS level. Most custom firmwares come pre-rooted. That is, they contain the software needed to allow you to escalate your priveledges to root level. Stock firmwares, do not have this additional software, and anytime you get an update for stock, it will replace everything you had with your previous install, which will make you lose root if you had it.
So, if you install CM7, it will be rooted, but if you restore your stock 2.3.4, it will become unrooted (because it was unrooted when you made the backup).
What is your final plan for software on the phone? Stock 2.3.4, stock 2.3.4 with root, CM7? What is the point of restoring your nandroid of 2.3.4?

UnaAble to root Nexus One

im useing ota 2.3.4 and ive tried everything to root the nexus one universal,z4,gingerbreak i have the bootloader unlocked but it will not root however gingerbreak did install su i thought my G2X was a trip this thing is giveing me more grey hair somew one have a solution

I had this problem and just managed to figure it out today (through the power of google). Superboot, oneclick and gingerbreak all don't work for 2.3.4 as of right now, so you have to use the PASSIMG method to flash an older version and root from there.
I found a good guide, but given that I've been a lurker for the past couple years as opposed to a regular poster, I can't link it. In lieu of a link, I suggest a search query such as "root 2.3.4 nd1razor"

Your bootloader is unlocked. No need for all that crap. Put the su zip on your sd card. Flash custom recovery via fastboot. Boot directly into the new recovery. And flash the su.zip from the recovery. You're rooted. The end.

you just need to flash custom recovery via fast boot or rom manager.then you can flash custom roms (which mostly have root along with tweaks) via recovery
Sent from my sexy nexy

I also unlocked the bootloader!
I put this ROM:
http://forum.xda-developers.com/showthread.php?t=1084726
But I still do not have root permissions ... Why?

You have them, but probably don't know how to use them. How do you check for them?
How did you put the ROM? Did you flash custom recovery?

Yes, i flash recovery-RA-passion-v2.2.1.img
Now my rom is: MIUI-1.9.16
The strange thing is that I managed to install the rom and recovery without having root permissions

Not strange. You don't need root. You have unlocked bootloader......

albundy2010 said:
Not strange. You don't need root. You have unlocked bootloader......
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Click to collapse
Thanks, you're very kind!
How do for get root permissions ?

The ROM includes them. When you're inside the ROM, you have root.

You are right !!!!! I just had to change the parameters with superuser
thanks
P.S.: Sorry for my ignorance