Questions tagged [debian]
Debian is a popular and influential GNU/Linux distribution. Questions here should generally be about Debian Server.
7,624
questions
362
votes
5
answers
154k
views
Anyone else experiencing high rates of Linux server crashes during a leap second day?
*NOTE: if your server still has issues due to confused kernels, and you can't reboot - the simplest solution proposed with gnu date installed on your system is: date -s now. This will reset the ...
- 1,738
262
votes
11
answers
268k
views
How can I run Debian stable but install some packages from testing?
Say you're running a server and you don't want to upgrade to Testing (Squeeze) from Stable (Lenny) to just install a required package or two.
What's the best way of installing only certain packages ...
- 8,573
234
votes
4
answers
182k
views
What's the best way of handling permissions for Apache 2's user www-data in /var/www?
Has anyone got a nice solution for handling files in /var/www? We're running Name Based Virtual Hosts and the Apache 2 user is www-data.
We've got two regular users & root. So when messing with ...
- 8,573
156
votes
6
answers
212k
views
List of files installed from apt package
How do I get a list of files that were or will-be installed when I apt-get a package? Conversely, can I find what package(s) caused a particular file to be installed?
- 2,066
143
votes
3
answers
51k
views
How to remove the "installed manually" flag and revert to "automatically installed" with apt-get?
To compile something, I needed the zlib1g-dev package to be installed so I launched an apt-get install zlib1g-dev.
apt-get informed me nicely that the package was already auto-installed because of ...
- 2,334
138
votes
13
answers
302k
views
How do I get apt-get to ignore some dependencies?
How do I make apt-get ignore some dependencies? For example, I wanted to install mailx so I can use it to send email from cron scripts/report-generating tools. However, installing mailx also installs ...
- 1,776
111
votes
8
answers
320k
views
How to install/change locale on Debian?
I've written a web application for which the user interface is in Dutch. I use the system's date and time routines to format date strings in the application. However, the date strings that the system ...
- 2,242
105
votes
8
answers
156k
views
How to determine JAVA_HOME on Debian/Ubuntu?
On Ubuntu it is possible to have multiple JVMs at the same time. The default one is selected with update-alternatives. But this does not set the JAVA_HOME environment variable, due to a debian policy.
...
- 1,422
105
votes
6
answers
128k
views
list all packages from a repository in ubuntu / debian
is there a command to see what packages are available from a certain ppa repository?
- 1,181
100
votes
9
answers
182k
views
mysqldump to a tar.gz
Usually after dumping a MySQL database with mysqldump command I immediately tar/gzip the resultant file. I'm looking for a way to do this in one command:
So from this:
mysqldump dbname -u root -p &...
- 1,181
99
votes
11
answers
151k
views
How can I export the privileges from MySQL and then import to a new server?
I know how to export/import the databases using mysqldump & that's fine but how do I get the privileges into the new server.
For extra points, there are a couple of existing databases on the new ...
- 8,573
95
votes
3
answers
40k
views
Is it possible to reboot a Linux OS without rebooting the hardware?
Is there a way to reboot a Linux system (Debian in particular) without rebooting the hardware?
I have a RAID controller that takes a bit to get itself running before the OS starts up, and I would ...
- 1,447
85
votes
8
answers
312k
views
How can I list my open ports on Debian?
What is the command to display a list of open ports on a Debian server?
I tried netstat -a | egrep 'Proto|LISTEN' but I would like something more specific that actually lists the port number.
- 989
83
votes
1
answer
49k
views
What does "debconf: delaying package configuration, since apt-utils is not installed" mean?
I have just installed Debian and I was just installing some packages using apt-get instal when I saw this message:
debconf: delaying package configuration, since apt-utils is not installed
What does ...
- 1,077
81
votes
5
answers
158k
views
Best location to keep SSL certificates and private keys on Ubuntu servers?
On Ubuntu, it looks like the best place for a private key used to sign a certificate (for use by nginx) is in /etc/ssl/private/
This answer adds that the certificate should go in /etc/ssl/certs/ but ...
- 1,677
80
votes
8
answers
73k
views
What should I do when I got the KEYEXPIRED error message after an apt-get update?
While updating my packages on a debian based system by a
sudo apt-get update
I've got that error message :
Reading package lists... Done
W: GPG error: ftp://ftp.fr.debian.org stable/non-US Release:...
- 4,164
78
votes
7
answers
27k
views
How to check for modified config files on a Debian system?
How to find all Debian managed configuration files which have been changed from the default?
- 1,711
78
votes
9
answers
118k
views
What is the debian-sys-maint MySQL user (and more)?
I have been bitten several times by the 'debian-sys-maint' user that is installed by default on the mysql-server packages installed from the Ubuntu repositories.
Generally what happens is I pull a ...
- 1,909
74
votes
2
answers
7k
views
How should an IT department choose a standard Linux distribution?
There is a lot of community feeling about what Linux distributions are appropriate for production server environments and which aren't, however, a lot of this feeling seems religiously based, and ...
- 6,938
69
votes
7
answers
43k
views
automate dpkg-reconfigure tzdata
I'm using puppet to admin a cluster of debian servers. I need to change the timezone of each machine on the cluster. The proper debian way to do this is to use dpkg-reconfigure tzdata. But I can ...
razor
68
votes
8
answers
146k
views
How to change a SSH host key?
I cloned a server and so they've the same RSA key fingerprint.
It seems to be defined in /etc/ssh/ssh_host_rsa_key.pub.
What is the correct way to change that?
Thanks.
- 1,443
68
votes
11
answers
185k
views
Disable a service from starting at all runlevels?
I have a service foo which currently starts at runlevel 3 and above. How can I stop it from doing so, without using update-rc.d foo stop 3 ., which (if I understand it correctly) would turn off the ...
- 1,611
68
votes
3
answers
262k
views
How do I enable non-free packages on Debian?
How can I enable non-free packages on Debian? I want to install Sun's Java JDK but it's not available to me.
- 683
68
votes
10
answers
106k
views
Question marks showing in ls of directory. IO errors too
Has anyone seen this before? I've got a raid 5 mounted on my server and for whatever reason it started showing this:
jason@box2:/mnt/raid1/cra$ ls -alh
ls: cannot access ...
jaymoo
66
votes
12
answers
223k
views
MySQL keeps crashing: InnoDB: Unable to lock ./ibdata1, error: 11
I have a simple webserver (Debian 6.0 x86, DirectAdmin with 1 GB of memory and still 10 GB free space, mySQl version 5.5.9), however the mySQL server keeps crashing and I need to kill all mySQL ...
- 1,483
66
votes
8
answers
61k
views
What steps do you take to secure a Debian server? [closed]
I am installing a Debian server which is connected directly to the Internet. Obviously I want to make it as secure as possible. I would like you guys/gals to add your ideas to secure it and what ...
64
votes
3
answers
54k
views
Docker: failed to add the pair interfaces (operation not supported)
After installing Docker, I am getting an error when I try to run the Hello World example:
Error response from daemon: Cannot start container ...
- 643
63
votes
4
answers
55k
views
Purpose of Debian "sites-available" and "sites-enabled" directories?
Can anyone tell me—in a nutshell—what the purpose of these two directories are in Debian?
/etc/apache2/sites-enabled
/etc/apache2/sites-available
I notice that diffing sites-available/000-default ...
- 732
63
votes
11
answers
17k
views
How Often Should I Update our Linux Server?
I am responsible for managing both our production server (mail, web, database are all on one server) and our test server. Both are built on Debian. However as I am very new to system administration, I ...
- 19.7k
62
votes
2
answers
44k
views
debian packages version convention
I'm using debian/Ubuntu, and get confused about versions of packages.
When using dpkg -l command, I get:
ii vim 2:7.3.429-2ubuntu2.1 Vi IMproved - ...
- 923
62
votes
5
answers
46k
views
What's the difference between 'useradd' and 'adduser'?
What's the difference between useradd and adduser? When/why should I prefer using one or the other?
- 929
59
votes
13
answers
69k
views
The following signatures couldn't be verified because the public key is not available: NO_PUBKEY
My environment:
# uname -a
Linux app11 4.9.0-5-amd64 #1 SMP Debian 4.9.65-3+deb9u2 (2018-01-04) x86_64 GNU/Linux
#
# cat /etc/*release
PRETTY_NAME="Debian GNU/Linux 9 (stretch)"
NAME="Debian GNU/...
google-cloud-platform
59
votes
8
answers
267k
views
Run a shell script as a different user
What's a good way of running a shell script as a different user. I'm using Debian etch, and I know which user I want to impersonate.
If I was doing it manually, I would do:
su postgres
./backup_db....
- 1,032
57
votes
6
answers
31k
views
Given a debian source package - How do I install the build-deps?
I have a debian (well technically ubuntu) source package, i.e. the .dsc, the .tar.gz, etc., I want to build this. The dpkg-buildpackage fails, since I don't have all the build dependencies.
Normally ...
- 31.9k
56
votes
9
answers
13k
views
What's the difference between apt-get and aptitude?
I don't get why there are two different programs in a minimal install to install software. Don't they do the same thing? Is there a big difference? I have read everywhere to use aptitude over apt-get ...
- 3,092
56
votes
6
answers
302k
views
How do I force Linux to reacquire a new IP address from the DHCP server?
The environment is Debian, although the answer will apply to all distributions.
55
votes
5
answers
86k
views
HAProxy graceful reload with zero packet loss
I'm running an HAProxy load balancing server to balance load to multiple Apache servers. I need to reload HAProxy at any given time in order to change the load balancing algorithm.
This all works ...
- 693
53
votes
12
answers
42k
views
How much SWAP space on a 2-4GB system?
How should I decide what size to make my swap on a new Linux machine (Debian) with 2-4 GB of RAM? Do I really need swap space?
- 3,095
48
votes
5
answers
29k
views
100% non-interactive Debian dist-upgrade
Is there a way to do an apt-get dist-upgrade in Debian that not only automatically answers "yes" to all questions asked, but also uses reasonable defaults as answers to questions that are ...
- 907
46
votes
6
answers
50k
views
How do you set a locale non-interactively on Debian/Ubuntu?
Usually, I run aptitude -y install locales then dpkg-reconfigure locales to set up locale.
Now I want to put it into a shell script, how can I reliably do the following, automatically / non-...
- 675
45
votes
2
answers
38k
views
Slow ssh login - Activation of org.freedesktop.login1 timed out
On one of my servers I've noticed really delay on SSH logins.
Connecting using the ssh -vvv options the delay occurs at debug1: Entering interactive session.
extract of connection:
debug1: ...
- 571
44
votes
2
answers
55k
views
Do some debian builds not have lsb_release?
A .deb package I am releasing expects that it can call lsb_release. One customer using Debian 6.0.5 indicated that the lsb_release command (even in the terminal) produces a command not found error. ...
- 1,116
43
votes
4
answers
128k
views
apt-get update/upgrade list without changing anything
I would like to view what packages are available for update/upgrade without actually changing any files becuase there are some packages I wouldn't like to update. Would it then be possible to apt-get ...
- 1,743
43
votes
6
answers
49k
views
How can I prevent cron from filling up my syslog?
I have a script which needs to be executed each minute. The problem is that cron is logging to /var/log/syslog each time it executes. I end up seeing something like this repeated over and over in /...
- 1,016
43
votes
1
answer
54k
views
What exactly will --delete-excluded do for rsync?
I use rsync with great pleasure for backing up my servers, although I do have a question about the --delete-excluded parameter.
/usr/bin/rsync -a --delete --numeric-ids --relative --delete-excluded ...
- 4,013
42
votes
5
answers
47k
views
Can dpkg verify files from an installed package?
With rpm -qV openssh-server I will get a list of files that have changed compared to default.
~$ rpm -qV openssh-server
S.?....T. c /etc/ssh/sshd_config
~$
Can dpkg on Ubuntu do the same?
- 10.4k
38
votes
7
answers
254k
views
Huge amount of TIME_WAIT connections says netstat
Okay, this is creeping me out - I see about 1500-2500 of these:
root@wherever:# netstat
Proto Recv-Q Send-Q Local Address Foreign Address State
tcp 0 0 localhost:...
- 589
38
votes
6
answers
262k
views
How to use both AllowGroups and AllowUsers in sshd_config?
I'm trying to modify /etc/ssh/sshd_config on my dedicated debian7 server with both AllowUsers and AllowGroups. However I can't seem get both to work together.
The Setup
There's a user called ...
- 483
38
votes
2
answers
18k
views
Can someone clarify Ubuntu (Debian) dist-upgrade for me?
I've got an Ubuntu 8.04 LTS server. There are several packages which are "kept back" ("the following updates have been kept back") when I do an apt-get upgrade. It's my understanding that I can do ...
- 5,008
38
votes
7
answers
97k
views
Unable to ssh to GCE: "Permission denied (publickey)"
I created a VM via Bitnami in Google Compute Engine. Previously, I was able to ssh via the Bitnami web interface. I tried to ssh via terminal on my Mac but kept getting the Permission denied (...
