Help Catch and save full catlog for boot.

[cdysthe]

Hi,

I am trying to figure out exactly what goes on when I reboot. I was told to do the following:

"Provide a full logcat from a boot. But don't do it on the device or after booting is complete. Use adb logcat started right after rebooting.

I see my phone when I do 'adb devices' and I'm able to start logcat on a running phone, but I'm not sure how to catch and save a full log during boot. What excatly do I have to do to catch the whole boot to a file I can share? I'm on Ubuntu with all the Android stuff installed and working.

//C

 

[iowabowtech]

Just go ahead and enter the adb logcat command into terminal, then press enter while the phone is rebooting. It will then say "waiting for device" and somewhere near the splash screen, the log will take off and run. That's the best you can get and should be what they are asking for.

 

[scary alien]

^^^ +1 to @iowabowtech's answer .

Also, if you do invoke the adb logcat command shortly after the reboot, you will / should be able to see all of the messages logged since the reboot (you'll be able to tell from the first messages logged).

Note that there is a ton of other stuff that actually happens that the kernel logs separately, but you likely cannot see or retrieve those messages unless you are rooted.

Chainfire has a really cool, root-only app called LiveBoot that can display kernel and/or logcat messages to your device's screen while it's booting-up. This is mainly useful as a cool boot animation (in fact it replaces your normal boot animation) but can be useful in some debugging circumstances.

Cheers!

 

[BustaLime]

Liveboot worked for me. It show's at boot time but has a setting to write a log file.

 

[cdysthe]

^^^ +1 to @iowabowtech's answer .

Also, if you do invoke the adb logcat command shortly after the reboot, you will / should be able to see all of the messages logged since the reboot (you'll be able to tell from the first messages logged).

Note that there is a ton of other stuff that actually happens that the kernel logs separately, but you likely cannot see or retrieve those messages unless you are rooted.

Chainfire has a really cool, root-only app called LiveBoot that can display kernel and/or logcat messages to your device's screen while it's booting-up. This is mainly useful as a cool boot animation (in fact it replaces your normal boot animation) but can be useful in some debugging circumstances.

Cheers!

Thanks! Installed the app and I see the message scroll by when I boot and I figured out how save it. So the log saved by LiveBoot is the same I would get from LogCat?

 

[scary alien]

So the log saved by LiveBoot is the same I would get from LogCat?

Since the logcat is the source, I would imagine that would be the case.

The entire contents of the actual system log are still available to you as long as you don't wait too long to snag it after rebooting. You can do this two ways:

1. From an adb shell:

adb logcat > c:\temp\my-saved-logcat.txt​

2. From your device using something like Android Terminal Emulator:

logcat > /sdcard/my-saved-logcat.txt​

You'll have to control-c out of the above command after a minute or two since the logcat command will continue to add to the file as long as you have the command running.