after typing this out more times than i can count,i have decided to make up a thread for it. hopefully this will end some of the confusion about fastboot booting recovery,why its better,and what you have to do if you opt not to take advantage of its benefits.
if you have not rooted yet, consider using the guide here,as ive tried to eliminate some of the confusion from htcdev's page,and using it will give you some basic knowledge and tools that you will use in happily modding your s-on device. youll also potentially have an understanding of fastboot boot
ing your recovery into phone memory,as it is the same thing as what the guide instructions are for a "temporary recovery".
most folks that have come from other devices are used to the following sequence of events:
2)install a custom recovery(generally clockwork mod,or Amon_Ra)
3)booting to that recovery to make and restore backups,flash roms,etc. since the root method generally gave access to all the phones different memory partitions,many of wich are modifiable via the custom recovery.
even worse,are folks who have come from different devices and used an app called "rom manager
" to manipulate things from within the booted operating system. i am not a fan of rom manager period,even on phones that it works on.
unfortunately,the above is a recipe for disaster on any s-on,high end htc device.
a few words about htcdev
htcdev is htc's answer to the publics cry for unlocked bootloaders,and the ability to modify and install custom operating systems on their htc devices.
basically,you send information to htc,and they provide an unlock token that is reusable,but unique to your device. this changes the locked
lettering at the top of your hboot screen to unlocked
,and gives you access to the /boot,/system,and /recovery partitions only
of your phone. it is not s-off by any means,and there are still alot of checks being done by the phone,wich lead to disadvantages. most notably,you cannot change any other partitions. hboot,radios,and splash screens are protected and off limits. you also cannot roll backwards in software build numbers and firmware if you flash a leaked rom and dont like it.
there are a couple of advantages.
1)unlike the underground exploits used in the past,htcdev will always work. you dont need to worry about unrooting and not being able to root again. if you need to relock your bootloader and flash factory firmware,you will always be able to re-unlock with your original unlock token.
this makes it convenient for users that only want root access so that they can run a few root apps(titanium backup,wifi tether) and delete some bloatware. the folks that like to run stock,and recieve OTA updates can easily do so by keeping the STOCK recovery on the phone.
as long as the stock recovery is in place,you are not in danger of an OTA messing up your phone.
: but,wait! wont accepting an OTA break my root?!
: yes,but thats not a big deal. after the OTA has finished,you can quite easily relaunch your temporary recovery,and re-flash your root files,just as you did when you first rooted. re-rooting is easily accomplished,and therefore nothing to be concerned with.
2)the other big advantage of an htcdev unlocked
s-on bootloader,is that since the bootloader is protecting itself,and the radios,it is nearly impossible to hard-brick(i.e.,unrecoverable) device with software flashes. any damaged to the phones filesystem are almost always fixed by RELOCKING the bootloader,and running an RUU(factory signed software package)
modding your s-on,unlocked device
first and foremost,remember this:
**an htcdev unlocked phone CANNOT write to the /boot partition FROM its /recovery partition.**
what this means is that,unlike your s-off evo 4g,thunderbolt,inc 1,or just about any other htc device you may have messed with,the rom that you flash from a recovery that is permantly installed on your phone cannot install the boot image.
since the boot image houses the kernel, the roms kernel is not being installed along with the rest of the rom.
this means that if your rom requires a different kernel than what is on your phone,it will not boot
. it will hang indefinately at the splash screen.
there are a couple options to work around this handicap with s-on phones:
1)use juopunut bear's tool to s-off your phone.
doing this makes your phone and recovery act like you are used to(recovery [I]can[/[I] write to /boot) but does not come without consequence. see this post for more info: http://androidforums.com/evo-3d-all-things-root/636832-scotty58-universal-rooting-guide.html#post5113887
2)flash the kernel manually. it can be done with the command fastboot flash boot
or it can be done by placing the boot image inside a PH98IMG file and flashing it in hboot.
PH98IMG flashing is a PITA on an s-on phone,in my honest opinion. the information on the "android info" text document inside the file must
contain the correct info or the phone will not let the file flash. this leads to much aggravation,confusion,and an overall very bad rom flashing experience
therefore,the better way to flash kernels,IF you want to do it manually,is to use the fastboot flash boot
command. more info on that here: [HOW TO] manually flash roms
and now the best for last:
3) fastboot boot your recovery into phone memory
this involves,basically,placing your recovery image inside the folder that contains adb and fastboot,booting the phone to fastboot,and the launching recovery into phone memory by entering the command:
fastboot boot recoveryname.img
do not confuse this with the fastboot flash
is taking an image,and booting it right up on the phone.
is permantly installing an image into the phones filesystem.
*if you use fastboot boot to launch your recovery into phone memory,then recovery CAN write to the boot partition,making rom flashing on your s-on device just like rom flashing on an s-off device.
i.e.,launching recovery from fastboot lets the rom install the kernel,and requires no seperate kernel flashing. this means that when you are following a rom developers install instructions,you can follow the set for s-off devices.
why does this work?!
well,an oversimplified explanation is this:
-fastboot is part of the bootloader,wich can write to the /boot partition
-launching recovery from bootloader,makes the recoverys operations work thru the bootloader.
-hence,launched recovery can write boot image. hooray!
all the above applies to bakcups as well. you canot restore a backup from the permenent recovery if it contains a different kernel. just like flashing a rom. all the above info in this post applies to restoring a rom as well.
last and not least,
some more detailed instructions
if you rooted with my guide,then you have seen this before. its basically the directions to "temporarily flash recovery"
for those that have rooted via other means,you can modify these directions to fit whatever folder you have adb/fastboot in,or you just use these directions:
download these files:
-Ext 4 recovery image: PG86IMG-recovery_ext_4.zip
first thing you need is drivers for adb to see your phone. if you have htc sync installed,you should allready have drivers. if not,you can install htc sync,or install these modified htc drivers
(i recomand revolutionary drivers)
-unzip your mini-adb.zip file. this is native funtionality in windows 7. you otherwise may need a utility such as "7-zip" to extract,or unzip it. place the unzipped
folder onto the root of your C\ drive on your PC(sorry, you mac guys will need to develop this for yourself,i dont have a mac). root means the top level,not inside any folders. so just copy and paste,or drag and drop the folder onto C with everything else that is there. rename it to "mini-adb_shooter" since youll be putting some 3vo(shooter) specific files in here. you actually can call it whatver you want,but directions from here forward will assume this folder to be named "mini-adb_shooter"
-open a command window. on windows 7,click the start bubble in the lower left and type "command" in the search box. xp i believe is similar or the same. doing this should open a small black command window.
-change to your mini-adb_vigor directory. type the following at the prompt in your cmd window:
2)launch a temporary recovery:
-move the image file from your downloaded zip file, and place it into the mini-adb_shooter folder.
-type in your cmd window,or copy/paste the commands that are in bold
-check the md5 of your recovery image:
i.e.,if youre using an image named shooter_recovery_ext_4
,then your command will be:
**make sure the resulting md5 matches any available listed md5 sums. **
(for the ext 4 recovery linked,the image md5 will be: aff934a272f6ba66cc19e8e4325506a8 )
-enable usb debugging on your phone and plug it in,charge only mode.
-check for connectivity:
-it should reply with your serial number. if so,then:
adb reboot bootloader
-this will boot your phone into "fastboot" wich is a white screen with coloered letters.
-check for connectivity:
-should return serial number
-temporarily launch your recovery to phone memory:
fastboot boot <recoveryname>.img
again,if youre using an image named as above:
fastboot boot shooter_recovery_ext_4.img
-youll see a (really fast) green status bar on the top right as your PC sends the recovery to your phone. youll then see the HTC
splash screen,then your recovery.
now that youre recovery is running,you have lots of options. you can mount usb storage to move things on and off the sd card if you need to. you can also flash the main version tool if you need to: main version tool
note that once recovery is running,you can unplug from the PC if you want to flash your rom from the couch,ktichen table,or wherever
you can now restore a backup,or flash a rom.
last and not least,a couple notes:
-to paste into the cmd window,you must right click/paste. you cannot control/v
-to copy from the cmd window,right click. click mark. highlight everything to copy in white. now hit enter,or right click again.
holler if you have more questions