I figured I would post a short after-action report of my experiences of having to reflash and rebuild my N900 from the ground up. I wanted to put this out here for a newbie that might get an N900, or, more likely, an old-timer who hasn't flashed and rebuilt from bare metal in a couple of years. This will hopefully be up to date for June, 2013. If anyone sees anything I missed/misspoke, please feel free to correct in-thread. I may consolidate and put this in a wiki page after it has been vetted by the community.

I. Background
My N900, after 3 years, finally gave up the ghost. I noticed that open mediaplayer was no longer seeing ogg-vorbis audio files, so a good percentage of my media was unplayable. Initially, I thought it might be due to a problem with the tracker, so I rebuilt the database, to no avail. When this had no effect, I thought it may be an issue with the ogg-support package. I decided to reinstall ogg-support, so at the command line, I did

Which nuked the N900. The upper left status bar was a pink box and all of the text was black boxes. Many directories in /opt (/home/opt) gave errors when listing them, "Stale NFS file handle"...

II Flashing
I decided since it had been so long, and since, while looking through talk.m.o, that several of the apps I was running (speedpatch, battery patch, etc) were no longer recommended. So I decided to "nuke and pave", flashing both the eMMC and the OS. Luckily, I had backups from before the device melted down.

Piece of advice #1 Set up a backup scheme for your device.

I am a Linux guy, and run primarily Debian. I have a number of boxes and VMs at home, one of which being a backuppc box. I have been backing up my N900 for years. Unfortunately, I was only capturing /root, /media/mmc1, and /home/user/MyDocs. My recommendation would be to capture those, plus /home/user, as well as the rootfs and optfs. Set up something (backupmenu!!!) which will capture the rootfs and optfs partitions. Another option would be to let cron grab them.

But I digress.

Flashing gave me problems, primarily because, I found out later, the OS flash (RX-51_2009SE_20.2010.36-2.002_PR_COMBINED_002_ARM.bin) was not executing. So I would reboot after a "successful" flash, only to have either "Icon missing" messages on the initial screen, or it would go straight to the main screen, which had the pink status bar and blocks instead of characters. Copernicus suggested pulling the battery between flashing the eMMC and the rootfs, as suggested on the Updating the Firmware page. This worked perfectly, and as it turned out, the rootfs was not actually being flashed in my earlier attempts.

III Post-flash configuration
So here I sit with a shiny, new(ish) N900, with the brand spanking factor (re)shine. Now what to do? In talking with some of you on the forums, speedpatch and batterypatch (both of which I was running) are frowned upon, as are, by some, overclocking, which was frowned upon. That said, the suggestions I got for "infrastructure" or performance apps were:

• CSSU/Thumb2
• Kernel Power
• Swappolube
• FlopSwap
• BackupMenu
• Busybox Enhanced
• Flash 12 fake

This lead to a slight stumble. I installed pretty much in that order, only to find out that CSSU/Thumb2 requires it's own kernel, 2.6.28.10-cssu3, so installing Kernel Power (50 or 52) will cause your N900 to reboot. Repeatedly. Doing innocuous things.

There may be another way to get the cssu kernel to boot after such a faux pas, but since the N900 does not have the grub I am used to from the Intel world, I just did the following:

This seemed to either a) overwrite the kernel, or b) re-order the kernels. (This is where you all should feel free to comment if you know... ) I also don't know the interactions between kernel power and the cssu3 kernel.

I also haven't installed busybox enhanced. I'm not sure whether or not I need this as I would prefer the gnu tools...I've already got gnu-tar installed, and being a Linux guy, I am thinking about coreutils-gnu, grep-gnu, sed-gnu, and any others I can find (awk? findutils? diffutils?). I don't want to break core functionality, but would prefer the GNU suite.

I also have a number of apps that I am considering playing with like truecrypt, and a few others, but not nearly the number of installed apps as I had installed before...Many of which I never looked at. My app catalog consists of

• Nokia Applications
• Nokia System Software Updates (which can probably be disabled?)
• Ovi (which can probably be disabled?)
• maemo.org extras
• community SSU (Testing)
• community SSU (Testing-thumb)
• Maemo extras-testing
• Maemo extras-devel (disabled)

I will probably re-enable extras-devel, at some point, but so far, I am very happy with my N900, it feels like a new device...Though, for the record, I still can't see oggs in mediaplayer, which makes me think it may be something in, perhaps cssu or something else? I'm just getting everything the way I like it, and reinstalling ogg-support seems like a Bad Idea for the moment.

Thanks to everyone who gave advice, opinions, and was generally there for me, answering dumb questions and the like.

I hope this rambling soliloquy may help someone along the way.

--vr

Well CSSU-Thumb will work with Kernel-Power as long as you use KP later than version 51r1. This has the required thumb erreta workaround.

Each of the things you have mentioned have there own wiki page.
So it's a good idea to have a look through each page before installing them. AFAIK most of the issues you found are covered in there own wiki somewhere.

I would disable extras-testing and extras-devel, then only enable extras-devel to download "foo" package and disable it after. This will speed HAM up during updates and stop it pushing unwanted update notices.

Also it's best to leave Nokia SSU enabled however you can remove Ovi if you like.

Lastly without ogg-support, you wont get ogg
If you are really worried about reinstalling it, do a full backup using the default backup and backupmenu to a uSD; then install.

That's good to know. I enabled extras-devel last night, and updated to KP52, but I immediately went back to -cssu3.

I concur with that. My intent for this post is to consolidate the process into one place, rather than having to go find a bunch of disparate wiki pages or multi-hundred-page discussions on talk.m.o. Ideally, I'd like to go back and add a bunch of links...

Actually, I personally, am running the middle ground. I have extras-testing enabled, but disabled extras-devel. But I've always lived dangerously, and run the majority of my machines on Debian/sid. Aside from the slower HAM, I might have left extras-devel enabled, because I have noticed simple things, like less, are only in extras-devel.

Speaking of command line tools, is (and why is, if applicable) busybox enhanced better than the -gnu packages (e.g. diffutils, findutils, sed, grep, awk, etc.)? And if I were to choose to install the -gnu packages, will they install cleanly over their busybox equivalents without breaking the remaining parts of busybox? I want to say I tried this with the N810 years ago, and that it was less than successful...but I don't remember the details. And that was probably a much earlier version of the tools and busybox.

I have ogg-support installed, but still, I can't see my ogg-vorbis albums in mediaplayer. I'm thinking about uninstalling ogg-support in favor of multimedia-pack.

Done and done. I may set up a cron job to do backups of rootfs and optfs, so that it is backed up automatically.

Thanks for your comments, sixwheeledbeast.

I heave a Noob question, but you seem seasoned.
https://wiki.maemo.org/Talk:N900_The_Perfect_Setup says "cssu-thumb contains a kernel based on kp51r1, therefore you automatically benefit from all kernel-power features (undervolting, overclocking, framebuffer, ...). See Kernel Power Wiki and Kernel Power 51r1 on tmo"

If this is true if i install CSSU on my n900 will i still need to install enhanced kernel to overclock it?? please answer. it would be helpful.
Message 26 of 26 (2 Views)

Firstly, I wouldn't consider or recommend an overclock.
Secondly if you which to overclock you need the latest KP which is KP52 and kernel-power-settings.
Finally the post above is regarding KCSSU which is a stripped version of KP with no overclocking.

@sixwheeledbeast: wrong, KCSSU is NOT a stripped version of KP, it supports everything KP51r1 supports, excluding uninstaller.

Ok this is what I thought was mentioned in the Thumb thread.
So why have two names for the same thing?

because CSSU cannot depend on external repos. Also, kcssu replaces omap1, while KP does not

Thanks for the answer. I was considering overclocking because I was interested in playing some webOS games that i heard run better if you OC the phone. I'm still learning about my n900. didn't mean to sound foolish.

Overclocking can be useful for some things, but depending on your device it may or may not promote instability. I have one N900 that overclocks to 900Mhz without issue, minus it getting warm when running at that speed. The second, anything over 600 and I find fs/memory corruption on the uSD card (and sometimes internal fs) if written to a lot while overclocked.

Generally overclocking is useful for short bursts. Going to a flash-heavy site to do image uploads? Turn it on for that for a short time, then back to stable before it goes in the pocket. Running at higher all the time is asking for trouble, as is running at high rates for > 10 minutes or so, since it's not designed to dissipate the heat that makes. There are tons of examples in the forums/wiki for desktop widgets or settings apps that allow this with ease. Queen Bee Widget being one of more popular.