Re: / 100% used

[Beco <rcb@beco.cc>]

On 6 July 2015 at 12:03, Marek Salwerowicz <marek_sal@wp.pl> wrote:

Hello Beco,

<cut>
Did you read  Jessie release notes before upgrading and upgrade procedures?
https://www.debian.org/releases/stable/amd64/release-notes/index.en.html

Since you teach students, it would be good to teach them "best practices" by running well organised and prepared server...

I'd re-think the partition layout:
https://www.debian.org/releases/lenny/ia64/apcs03.html.en, second paragraph:

For multi-user systems or systems with lots of disk space, it's best to put /usr, /var, /tmp, and /home each on their own partitions separate from the / partition.

Are there any backups / RAID for users' home directories?

Please don't consider it as offensive, I'd like just to let you know that the problems you've encountered could have been much worse

Good luck  ;-)

Cheers

Marek

Hi Joe, Marek, guys,

Joe, I prefer not to disable it on the bios. I like to have some control over ssh. You never know. But after blacklisting it, I think the problem is solved for a while.

Marek, thank you for your kind criticize. Most people don't get how to politely point problems without being rude (I'm one, but mostly because the english barrier, I tend to be dry).

> Why have you performed major upgrade of Operating System on running production server?

Well, I had no choice. This server can't go down, and needs to be up to date. 

But I scheduled to vacations period. Users drop from 200- to almost zero. Never zero. This days, there are only 6 students left, 3 of them online. I am responsible for them as well. But being so many, I could help if things get very wrong.

Thanks the system was down only for 2 non-consecutively hours. 1h, when the problem appear, solved with a "while loop", and 1h when the next attempt failed (removing wpasupplicant). This last one was horrible, because it took me from home. Now its running using ifdownup. I think I'll let it this way for now. Until things are sorted out by Debian maintainers of what went wrong after upgrade. I still believe there was some misconfiguration issue regarding NetworkManager, specially after my notebook also broke.

> Did you perform backup of data before performing upgrades?

> Did you try it before on any development machines?

Yes, I set up a backup server. It is used to test upgrades also. I upgraded it some weeks ago. No problem at all. I was quite amazed it worked flawlessly. 

But there are no backups during vacations, because students get out every 6 months and accounts are deleted after that. So home is almost empty (you can see that in the `df -h`)

But to substitute one server to other in case of problems would take at leas a day or two of hard work. Not a good option.

Also, all users (but this 6) are locked out. And only 3 are heavily using. Even those 3 did not lost any data or work. That was a very good upgrade, despite this 2 hours down.

Next time, Debian 9 will not let me down! :)

(And, yes, I read the release notes -- not again, but when upgrading the first system).

Anyway, thank you for the tips. I will consider changing /var to another partition. 

(*) Given my current set up, I think its better to bring some space from /home, isn't so? How many Gigas would you use (given this particular case in hands?)

/dev/sda1        46G   12G   33G  26% / (ext4)

/dev/sda3       864G  4.0G  816G   1% /home (ext4)

Current usage:

$ du -hc

var = 1.1 GB (ext4)

usr = 8.5 GB (ext4)

tmp = 200 KB (ext4)

I'm thinking of:

var = 10 GB

usr = 20 GB

tmp = 10 GB

Or maybe:

var = 15 GB

usr = 20 GB

tmp = 5 GB

And keep all ext4 (to simplify my life, if that is ok, or at least not critical).

(**) What configuration tool do you suggest to use for partitioning? Is it safe to do it via ssh?

(***) Should I trust better NetworkManager, or let the server using ifupdown? Or change to Wicd?

Thanks

Beco.

--

Dr Beco
A.I. researcher

"I know you think you understand what you thought I said but I'm not sure you realize that what you heard is not what I meant" -- Alan Greenspan

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