Kernel question

[3ibs]

I'm about to flash Lean Kernel and I made a nandroid backup just in case. Do nandroid backups backup EVERYTHING? If I were to restore to the backup after flashing lean kernel I would go back to the kernel I had before? I'm on AOKP b27 with it's stock kernel (at least I think that's the kernel I'm on since this is the first kernel I flash). If I decide to flash another kernel, say Franco kernel, can I just flash it over lean kernel?

Another question. When do I need to do a dalvik cache wipe and what does it do? I did one just now in CWM recovery mode and it said E:unknown volume for path [sd-ext]
Does that mean it's only for phones that have an external sd card?

Edit: I just flashed it and don't notice anything different other than the Kernel version changing in About phone. Is it supposed to add something in Settings that I can configure.

 

[zero neck]

Nandroid backups will back up your rom, your kernel, and your cache - but not your bootloader or your radio.

Dalvik should be cleared every time you flash something in recovery.

sd-ext is a partition in your sd card that your phone is capable of using but does not regularly use - so it gets checked for backups but its not in use, so it it's E:unknown for now. Dont worry aobut it, its normal. This applies to phones with sd cards and without (the gnex, tho it has no actual sd card, has an internal memory that is delagated "sd card")

Not sure what you mean about kernel version changing things - it changes the kernel you have. Some kernels do more than others, might have a more visible presence in a way, but in general, kernel is under the hood stuff -kernels determine what and how much power things get (put very, very simply).

Rule of thumb for flashing and wiping - in recovery mode
flashing a rom - wipe data, cache partition, dalvik cache, format /system
flashing a kernel or a theme - wipe cache partition, dalvik cache, format /system
flashing a radio - wipe cache and dalvik and format system

 

[DaRkL3AD3R]

Format /system? On a radio/kernel install? Not exactly good advice...

 

[Phazenine]

Format /system? On a radio/kernel install? Not exactly good advice...

Agree

Sent from my i9250 (GSM) Galaxy Nexus.
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