LM 20.3 Cinnamon: Login Loop

[borgward]

Linuxmint Cinnamon 20.3
I start the computer, Login appears, enter the password and press Enter. Login appears again, I enter password and repeat. Desktop never appears. Never get Invalid Password message. I entered a wrong password and get Invalid Password message.

Shutdown completely. Waited 30 minutes. Started computer. Login worked.

I could have been typing in the password incorrectly, but why did I not get the Invalid login message?

[SMG]

Normally, the two main reasons one gets stuck in a login loop are a full root partition or a corrupt authority file as explained in this post.

I'm not sure what may have happened in your case, but I suggest checking to see how fully your root partition is--just in case it is close to full.

[borgward]

/ was pretty full. I recently got notice to that effect and was booting up as I suspected that kernels needed pruning. / is 30 GB. I now have 3.7 GB free after removing kernels. That still does not seem like a lot of headroom.

[SMG]

I believe the criteria goes by percentages and not absolute values. The values you listed puts you ~88% full.

If I am recalling correctly, the warnings start ~90% and when you are close to ~95% is when the system will not let you log in.

[borgward]

My other computer has 750 GB HDD with 57 GB /. Root contains 20 GB. It is my daily driver and have been using it for years. The one that had Login problem has 1000 GB HDD with 30 GB in / . Root contains about 26.5 GB. It is not used much so I either look for things to remove from / or else increase / to about 60 GB. Does not seem right that has about 6.5 GB more than in root in my daily driver.

[borgward]

I see that timeshift is taking up 15.8 GB of /. I either get rid of timeshift (if that's possible) or increase / to about 60 GB.

[smurphos]

I see that timeshift is taking up 15.8 GB of /. I either get rid of timeshift (if that's possible) or increase / to about 60 GB.

Or don't use / for your timeshift snapshot storage. It's GUI allows you to select a different partition.

[SMG]

I see that timeshift is taking up 15.8 GB of /.

It is not the Timeshift application which is taking up that space. It is the snapshots which are using that space. As smurphos has indicated, you can save snapshots to locations other than /. The default is to save them to /, but you can save them to other partitions or drives, including external drives which is what I do.

Or you can increase the size of / if you have room to do that. Either way can work.

[borgward]

I had timeshift set for 5 daily snapshots. I deleted 2 and reset for 3 daily snapshots. Timeshift now occupies 15.1 GB and I now have 5 GB free in /.

How do I calculate how much room I need in / for each daily snapshot? I realize the size of root (not considering snapshots) is going to be dynamic, so just a rule of thumb. For each GB in root I need how much space for each snapshot?

This machine is not my daily driver so I decided to try out Snapshot before using it on my other machine. I will probably go back to 5 daily snapshots eventually.

[smurphos]

The base snapshot will be effectively the usage of the rest of / at that point in time. How much space subsequent snapshots take depends on what has changed in the interim - basically log changes and changes as a result of software installs, removals and updates, so they will generally be much smaller as only the changes are saved.

For example my / is currently about 12G. I've got timeshift saving snapshots to an external drive with loads of space - so 10 snapshots (going back to beginning if December) take up 28G - bear in mind this period includes an update from 20.2 to 20.3 (so a relatively large upgrade) and I also trimmed significantly the maximum size of my journal in that period so the oldest snapshots were based on a roughly 15G /). I'd guess 28G is probably more than my 'long term' average would be for 10 snapshots. A fair rule of thumb would probably be to allow 10% of the of the / usage for each additional snapshot you want to save, maybe a bit more if you intend to keep older monthly or weekly snapshots.

I would urge you to consider using external storage for your snapshots - it makes much more sense (including in terms of recovery from serious disaster like drive failure). A 32GB thumb drive be sufficient.

If you continue to use / limiting yourself to 2 or 3 snapshots is a good idea. Also consider a fairly regular routine of using apt autoremove && apt clean to save space. You can also save a lot of space (both in / and your snapshots) by limiting the size of your journal (by far the biggest space eater in /var/logs/) - e.g mine is limited to 1 month of logging by creating the file
/etc/systemd/journald.conf.d/00-smurphos.conf with content

Code: Select all

[Journal]
MaxRetentionSec=1month

[SMG]

I had timeshift set for 5 daily snapshots. I deleted 2 and reset for 3 daily snapshots.

Timeshift is part of a strategy to restore your system files should something happen. It is not a backup of your drive; it only backs up system files. I mention that because on a system you are not using frequently, you may not need to be taking many snapshots.

I personally take a snapshot manually on my daily driver computer once every few weeks or if I am making a change that might have the potential to cause issues. I save my snapshots to an external usb using the methodology described in How to Use Timeshift to Backup and Restore Linux Mint 19 Systems from USB Drive.

However, I also have access to a pretty good internet connection so reverting to an older snapshot and then adding new updates which have come along since then is not a big issue for me.

Consider Timeshift as one part of your overall strategy.

[cliffcoggin]

I see that timeshift is taking up 15.8 GB of /. I either get rid of timeshift (if that's possible) or increase / to about 60 GB.

The better solution would be to move Timeshift snapshots to home or an external device. Anywhere but root.

[borgward]

I forgot to mention that my computers have a separate Home partition. So I use timeshift to restore / only. What do I use to backup or restore my separate Home partition? I would use a thumb drive for /, and a large external HDD to backup or restore Home?

If I use 5 daily snapshots, Is the first one always retained?

[cliffcoggin]

I forgot to mention that my computers have a separate Home partition. So I use timeshift to restore / only. What do I use to backup or restore my separate Home partition? I would use a thumb drive for /, and a large external HDD to backup or restore Home?

If I use 5 daily snapshots, Is the first one always retained?

Yes, Timeshift is for system backup only, but until you move the snapshots out of root, as three of us have now said, you will not resolve your problem.
Any of the snapshots can be deleted at will using the Timeshift application. (It is not recommended to do it from the file manager for reasons I do not understand.) There is no need to keep the first. If you set a schedule this will be done automatically.

Data backups (Home) should be done with a complementary tool such as Back In Time, Lucky Backup, Grsync or another of your choice.

[borgward]

I am setting up Timeshift on my daily driver:
Type rsync
Location sdb1 - a 32 GB USB stick
Daily Keep 3
Users /home/me Exclude All Files (Default)
/root Exclude All Files (Default)

This is the right way to go?
Wondering what the other options, Include Only Hidden Files, Include All Files are for?

[SMG]

I am setting up Timeshift on my daily driver:
Type rsync
Location sdb1 - a 32 GB USB stick
Daily Keep 3
Users /home/me Exclude All Files (Default)
/root Exclude All Files (Default)

This is the right way to go?
Wondering what the other options, Include Only Hidden Files, Include All Files are for?

Please create a new topic for these questions. These questions are not related to Login loop issue which is solved. It is easier both for those helping and those searching in the future to keep topics focused on specific issue which is why we have in the rules and guidelines New Questions Deserve New Topics.