force ubuntu/debian netinstall to use a specific variant of debian-installer or specific udeb file versions

force ubuntu/debian netinstall to use a specific variant of debian-installer

i've run into various changing bugs with the udeb distribution.
over the time, the ubuntu maintainers change stuff and in the end there is no way to get something reliable.
installs became sluggish since a kernel hange in january, now thy switched to a new version of glibc ( 2.23-0ubuntu11 with the introduction of known bugs dating from years ago ) which breaks the installer by producing segfaults.

does any of you know a way to use an older version of udeb in preseed ?

i know i can setup my own debian mirror, but i'd need to mirror both the udeb and the deb part. i'm ok to mirror udeb alone if that is feasible but AFAIK preseed only offers a single choice for package sources. maybe there is a way to use local files i can grab on an older ISO for udeb only ?

ideas ?

btw, i'm installing ubuntu-xenial should that matter.
yes i know it is outdated. no i do not currently have a choice in this case. please do not discuss that point.

thanks for your help
LVL 28
skullnobrainsAsked:
Who is Participating?
I wear a lot of hats...

"The solutions and answers provided on Experts Exchange have been extremely helpful to me over the last few years. I wear a lot of hats - Developer, Database Administrator, Help Desk, etc., so I know a lot of things but not a lot about one thing. Experts Exchange gives me answers from people who do know a lot about one thing, in a easy to use platform." -Todd S.

skullnobrainsAuthor Commented:
actually a simple way would be to stick working udeb files in the tftproot.

that is easy. what i don't know is how to ask the installer to actually load those files rather than downloading them from the internet without also loading the base system from the same location
David FavorLinux/LXD/WordPress/Hosting SavantCommented:
Tip: Stick with LTS releases for greatest stability.

Bionic is latest LTS, so will be your most stable starting point.

You can use Xenial, keeping in mind Xenial hits EOL (end of life) in around 12 months, so only 12ish more months of updates.

Usually .udeb files work the same as .deb files + disk space is super cheap now, so you might try working with a standard install rather than a micro install (.udeb files) as only difference is stripped out documentation... if the doc strip was done correctly...

Here's how I resolve problems you're describing across 1000s of Ubuntu installs... which I have zero problems running...

1) At the machine level install Ubuntu Bionic + SNAP LXD.

2) Create LXD containers for running applications.

3) Containers can be Ubuntu, with documentation stripped. You can also use Alpine in containers, which is BusyBox based with a very small footprint.

4) When you run machine level updates, LTS version updates tend to work very well, because 1,000,000s of LTS versions are running + if there's even a whiff of problem... 1,000,000s of installs would break... so LTS updates tend to be rock solid.

5) To install major updates in containers. Stop container. Clone container. Start clone. Run update in clone. If update fails, destroy clone + start again. So you always preserve your production containers/sites.

When you say, "i've run into various changing bugs with the udeb distribution", remember .udeb files receive far lest testing + use than .deb files, so .udeb files (to me) are always suspect, because I require 100% stability... all day... every day...
David FavorLinux/LXD/WordPress/Hosting SavantCommented:
Maybe post an exact example of what "i've run into various changing bugs with the udeb distribution" might mean.

Someone may be able to provide a solution to problems you're experiencing.

Also, you can setup any time of custom repository you might like... This will just take a massive amount of time to setup, along with a large daily commitment for maintenance... if you're trying to vet + test every update... to every package... you've cherry picked for your custom repository.
Get a highly available system for cyber protection

The Acronis SDI Appliance is a new plug-n-play solution with pre-configured Acronis Software-Defined Infrastructure software that gives service providers and enterprises ready access to a fault-tolerant system, which combines universal storage and high-performance virtualization.

skullnobrainsAuthor Commented:
yes i know it is outdated. no i do not currently have a choice in this case. please do not discuss that point.

i'm installing on both bare metal and vmware so please stop with LXD. this is off topic.

i'm facing an issue with automated deployment using TFTPboot + netbootinst + preseed + xenial
these are requirements in this case. there is no point in discussing them.
i cannot use ghosts or filesystem templates either.
i cannot use non-official installers ( yes that's a pain given the quality of the official one )

i do have some latitude with the way i handle basic install. i can use a different protocol. http is quite easy. others require lots of work.

When you say, "i've run into various changing bugs with the udeb distribution", remember .udeb files receive far lest testing + use than .deb files, so .udeb files (to me) are always suspect, because I require 100% stability... all day... every day...

yeah, thanks for sharing. given a choice i'd probably be deploying openbsd on freebsd-based bhyve hosts. unfortunately, i have to bother with the above fine^^ technologies

... which is why i'd like to stick with a working set of udeb files since an uptodate installer won't do anything an older one will not and could probably be updated manually once in a couple of years or so.
David FavorLinux/LXD/WordPress/Hosting SavantCommented:
Best to provide an actual example of what "i've run into various changing bugs with the udeb distribution" might mean.

Good chance there's a simple solution.
skullnobrainsAuthor Commented:
the latest problem was the whole minios becomes unusable after installing libc6-2.23-0ubuntu11 which segfaults due to a well know bug in 2.23 corrected in debian mainstream in 2015. it did work with ~10

previous bugs mainly introduced sluggishness in different parts of the install process. delayed by hours during a previous kernel update.

my goal is not to correct each bug as they come.
i have no trust in ubuntu's maintainers, and i'm pretty sure such bugs will arise again.

i want to stick with a working variant of the minios and update manually the minios from time to time rather than rely on something i have no control over.

what i need to do is integrate a working version of the minios repository ( that should not be too hard and ican mirror the whole udeb distribution which is rather small ), and instruct the netinstaller to use the corresponding local ( tftp or possibly nfs-based ) or local web repository.

this should also speedup the install process

what i do not know how to achieve cleanly is switch to the regular repositories AFTER the minios is installed and BEFORE the actual install process starts.

preseed has an undocumenter feature "di network/live-installer" ... that does not work.
the regular option to switch sources applies to both the minios and what is actually installed on the machines + sets repositories and i have no wish to mirror the regular debian repositories.
skullnobrainsAuthor Commented:
this is the bug i hit
https://bugs.launchpad.net/ubuntu/+source/debian-installer/+bug/1816876

it has been hitting every single pxe-based unattended installation of xenial for everyone since the 5th of february

the ubuntu maintainers attempted to close most of the numerous bug reports without even a decent check.
skullnobrainsAuthor Commented:
i found various solutions including the following reasonably simple ones.

1/ publish a different package.xz
grabbing the one from a different debian version works at least in some cases.

2/ use the partman/early_command hook to change sources.list

both of the above provably work but i have not used them extensively since i implemented deployment from templates at the same time in order to solve the immediate problem at hand faster.

Experts Exchange Solution brought to you by

Your issues matter to us.

Facing a tech roadblock? Get the help and guidance you need from experienced professionals who care. Ask your question anytime, anywhere, with no hassle.

Start your 7-day free trial
It's more than this solution.Get answers and train to solve all your tech problems - anytime, anywhere.Try it for free Edge Out The Competitionfor your dream job with proven skills and certifications.Get started today Stand Outas the employee with proven skills.Start learning today for free Move Your Career Forwardwith certification training in the latest technologies.Start your trial today
PXE Boot

From novice to tech pro — start learning today.