La Salle Debain

Open Source @ Consolidated Braincells Inc.

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About La Salle Debain

This is a weblog I'm keeping about my work on Debian and any other useful Debian related info I come across. It is not meant to compete with other news sources like Debian Weekly News or Debian Planet. Mostly it is just a way for me to classify and remember all the random bits of information that I have floating around me. I thought maybe by using a blog it could be of some use to others too. Btw. "I" refers to Jaldhar H. Vyas, Debian developer for over 8 years. If you want to know more about me, my home page is here.

The name? Debain is a very common misspelling of Debian and la salle de bains means bathroom in French.

If you have a comment to make on something you read here, feel free to write to me at jaldhar@debian.org.

You can get an rss 0.91 feed of the blog here.

Monday, November 7 2016

New Laptop / Problems with Windows part 896,324

I had mentioned previously that I had been forced to purchase a new laptop. I decided that I didn't want another Thinkpad. The Lenovo ones no longer have the high quality they had in the IBM days and while support is still pretty good by todays dismal standards it's not worth the premium price. (If I'm buying it with my own money that is.) I had heard good thing about Dells' Linux support so I looked into their offerings and ended up buying a Precision 7510. Mind you this model came with Windows 7 installed but I didn't mind. As I wanted to install Debian according to my own specs anyway, I was ok with just knowing that the hardware would be compatible. So I prepared a Jessie USB installation stick (This model doesn't have a CD/DVD drive.) and shrunk down the Windows installation (but not deleted it altogether for reasons to be explained below.)

At this point it is traditional to give a long, tortured account of how Heaven and Earth had to be moved to get Linux installed. But that is a thing of the past. The combination of good hardware and the excellent work of the debian-installer team, made the setup a breeze with only a couple of minor bumps in the road. One is that the kernel on the Jessie cd was not quite up to snuff. Downloading 4.6.0 from backports did the trick. Post-install, to get the most out of my nifty new 4K display, I needed the latest, alas non-free, nvidia-drivers. And for stable wifi (I always install over ethernet for this reason) I had to install the firmware-iwlwifi package. Everything else—even my printer—either "just worked" or needed only minor fiddling around.

Having used this machine for a while, the biggest problem I have is with the keyboard. It is nowhere near as tactile and comfortable to use as the old IBM Thinkpads. Even Lenovo Thinkpad keyboards are better. I'm a hunt-and-peck type myself but it is annoying. I think a real touch typist would hate it. The cursor and home, end, page up, page down etc. keys are in the wrong place and home and end are actually function keys. There is a pointer and a trackpad and two sets of mouse buttons which seems like a waste of space. In fact much space is wasted everywhere, space which could be used to improve the keyboard. Other than that I like it. The battery life is not the best but fairly good. It's a bit heavier than I was used to but I've gotten used to it. Although I didn't go with the SSD option, it is not that noisy; again you can get used to it. All in all, I think it is worth it for the price.


I installed Debian but I only really use it as a base to run VMWare Workstation. I occasionally have to support software across multiple platforms but I don't want the hassle or expense of multiple computers so I have Windows (the original installation upgraded to Windows 10) and Mac OS X running in VMs. Plus I have another VM running Kubuntu LTS for my day to day computing, another Debian install running sid for packaging, and Minix. Backups are as simple as making a snapshot of the VM. If something accidently gets screwed up, I can easily revert it back to a known good state. Ideally, I would like to replace VMWare with a free solution such as qemu or virtualbox etc. but as far as I know VMWare is far ahead in emulation capabilities (OpenGL support for example.) which is vital for efficiently using the proprietary OS's.

Things were going swimmingly until a few days ago which brings me to part two of this post. I booted into the Windows 10 VM only to be greeted by a message from the Windows boot manager that "A component of the operating system has expired." I tried going back to a snapshot from September (when this definitely was working) but I still got the same thing. A bit of googling revealed this has happened to others and the advice seemed to be to reset the computers date and reinstall Windows 10. It took several tries but I finally got that done, completed the task I needed to do and shut it down. At the end of the day I shut the whole laptop down and thought no more of it.

The next day I boot up and...where is grub? It seems that during the Windows reinstall, it had overwritten grub with the Windows boot loader. And while grub is nice enough to add an entry for Windows when detected, Windows does not extend the same courtesy to Linux. Ok time to bring out my trusty USB stick again and reinstall grub. Oops I've wiped it off to store other things. No matter, download another image and do it again. Reboot and...back in Windows. Fiddle around in the EFI settings until I can get it to boot from USB.

Now i'm in the shell provided by debian-installer so I can mount and chroot my Linux partition and reinstall grub. Except no I can't because it is Luks encrypted. Ok apt-get install cryptsetup, open it with my passphrase and now I can mount the partion, chroot into and reinstall grub. Except no I can't because it is a logical volume group. Back to apt-get, install lvm2, vgscan (because of course I've forgotten the name of the group,) vgchange and now I can mount, chroot, etc. etc. Except no I can't.


# mount /dev/mapper/vg00-root /mnt
# chroot /mnt
# grub-install /dev/sda
error: cannot find a device for /boot/grub (is /dev mounted?).

sigh


# mount /dev/sda5 /boot
special device /dev/sda5 does not exist.

Well, /dev is mounted but it does indeed not contain a device called sda5.


# /etc/init.d/udev start
udev requires a mounted procfs.  not started.

Very well then.


# mount -t proc none /proc
# /etc/init.d/udev start

Nope. proc needs sysfs.


# mount -t sysfs none /sys
# /etc/init.d/udev start

Still no. You get a warning about how it is a bad idea to run udev from an interactive shell and there is still not /dev/sda5. Time to start googling again. It turns out what I should have done is open another shell from the installer environment and do...


# mount --bind /dev/ /mnt/dev

Now I can mount /boot/grub and reinstall grub and it should all work right?

I should be so lucky. Ok back to square one. I now did what I should have done in the first place and searched the Debian wiki. Sure enough there is a page which deals exactly with my predicament. Finally I get everything installed correctly and triumphantly reboot into Linux.

Of course now Windows doesn't work again...


posted at: 13:01:07 | #