I tried updating CyanogenMod 9 on my Galaxy Nexus. \u00c2\u00a0The first step is to perform a Nandroid backup. \u00c2\u00a0You can do that by powering off the phone, holding volume up and down and then power until the phone vibrates. \u00c2\u00a0This might take 15 seconds or so. \u00c2\u00a0The Android logo will appear on the screen with a big green arrow above it that says “Start”. \u00c2\u00a0Let go of the keys. \u00c2\u00a0Use volume down to select Recovery Mode and press Power. \u00c2\u00a0Select “backup and restore”, then “backup.”<\/p>\n
After loading the new CyanogenMod ROM<\/a>, the phone wouldn’t boot right. \u00c2\u00a0It would start, but not connect to the \u00c2\u00a0phone network. \u00c2\u00a0After a while it’d reboot itself. \u00c2\u00a0I’d had this problem once before. \u00c2\u00a0I rebooted into Recovery and tried a restore, but it failed with the message “Error while restoring \/data!” \u00c2\u00a0Googling recommends wiping the phone to factory state and reloading CyanogenMod.<\/p>\n The first step is to save the last Nandroid backup. \u00c2\u00a0To do this, start Recovery, then select “Mounts and Storage”, then “mount \/data”. \u00c2\u00a0Then connect the phone via USB to your computer and on your computer, change to the android SDK platform-tools directory and After the backups are secure, restore the phone to a factory state<\/a>.<\/p>\n When the phone starts in activation mode, just skip everything it asks for, then in settings, under developer options, turn on USB debugging. \u00c2\u00a0This will let you download su.zip:<\/p>\n
\n$ adb pull \/data\/media\/clockworkmod\/backup<\/code>
\nYou might have to run this command with sudo if you don’t have UDEV rules set up correctly. \u00c2\u00a0Each directory in backup is a Nandroid backup that has a TAR file of cache, data and system, a boot and recovery image and an MD5 sum.<\/p>\n$ adb push su.zip \/sdcard\/.<\/code><\/p>\n