Ubuntu Linux is a Debian derivative that aims to bring Linux mainstream. Questions on this site should generally refer to Ubuntu Server. Note that http://askubuntu.com is specifically dedicated to Ubuntu questions.

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63
votes
11answers
68k views

apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ServerName

I keep getting this warning when I (re)start Apache. * Restarting web server apache2 apache2: Could not reliably determine the server's fully qualified domain name, using 127.0.1.1 for ...
43
votes
3answers
15k views

.profile vs. .bash_profile vs. .bashrc

what are the functional differences between these guys?
16
votes
1answer
23k views
27
votes
9answers
11k views

Are configuration management tools (Puppet, Chef) capable of keeping installed packages up to date?

This is probably a simple question for those of you already running configuration management tools. Are configuration management tools such as Puppet or Chef the right approach for keeping installed ...
18
votes
6answers
64k views

How can I edit the welcome message when ssh start?

I have a vps for my website hosting. It is running a ubuntu server. Every time I logged in my server by ssh, it displays a lengthy welcome message in my terminal. Linux node61.buyvm.net ...
16
votes
5answers
4k views

Updating production Ubuntu boxes the dos and don'ts

Every so often I login to production web/db/tools boxes and see the typical message: 30 packages can be updated. 16 updates are security updates. My question is, how do all of you handle updates on ...
26
votes
3answers
21k views

Testing whether jumbo frames are actually working

Is there a command to test whether jumbo frames are actually working? i.e. some sort of "ping" that reports whether or not the packet was broken up along the way. I've an ESXi host with an Ubuntu VM ...
22
votes
6answers
20k views

Why can't I access my CouchDB instance externally on Ubuntu 9.04 server?

Update: I got it working now. Jim Zajkowski's answer helped me detect that my /etc/init.d/couchdb reboot calls weren't actually rebooting the instance. After I manually killed the CouchDB processes ...
18
votes
3answers
122k views

How to properly set permissions for NFS folder? Permission denied on mounting end.

I'm trying to connect to an NFS folder on my dev server. The owner of the folder on the dev server is darren and group darren. When I export and mount it to my Mac using the Disk Utility it mounts, ...
11
votes
3answers
56k views

How do I cleanly remove apache2 server on ubuntu server and then reinstall?

I am having some wierd issues with Apache2 server on my ubuntu server. I believe some configuration files may have been tampered with. What is the easiest way to remove apache2 completely from my ...
23
votes
3answers
13k views

gpg not enough entropy!

SO I've got a ton of processes running in the background to try and get enough entropy but I am still failing. **We need to generate a lot of random bytes. It is a good idea to perform some other ...
38
votes
5answers
3k views

How do I empty /dev/null? [closed]

I am using Ubuntu 10.10. I am generally good with computers but mostly with Windows, I'm not very familiar with Ubuntu. I'm trying to setup a website and I'm talking with a friend I have who works ...
34
votes
6answers
27k views

How do I permanently disable Linux's console screen saver, system-wide?

I've got an Ubuntu server that boots up in text mode. It rarely has a screen or keyboard attached to it, but when I do attach a screen, I usually have to attach a keyboard too, because the darn ...
28
votes
3answers
12k views

How can I check /dev/xvda1?

On login to EC2 (Ubuntu) instance, I see *** /dev/xvda1 should be checked for errors *** I can't fsck /dev/xvda1 because it is mounted, and sudo umount /dev/xvda1 fails because it is in use. lsof ...
27
votes
3answers
26k 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?
11
votes
3answers
10k views

Need to fix file permissions in a user's home directory

Does anyone have a tool or script that will recursively correct the file permissions on a directory? On an Ubuntu Linux machine, a bunch of files were copied to a USB disk with full 777 permissions ...
14
votes
5answers
29k views

Setting up RADIUS + LDAP for WPA2 on Ubuntu

I'm setting up a wireless network for ~150 users. In short, I'm looking for a guide to set RADIUS server to authenticate WPA2 against a LDAP. On Ubuntu. I got a working LDAP, but as it is not in ...
9
votes
2answers
14k views

How can I run Selenium tests on an Ubuntu server?

I currently have a test machine running Ubuntu server 9.10 with no GUI. I want to run my Selenium RC test suites which open Firefox and perform a series of operation. I could bloat my test server ...
7
votes
1answer
11k views

What user should own /var/www on Ubuntu 9.04 Server?

I've got LAMP on Ubuntu 9.04 Server and the default installation has root:root owning the /var/www folder. I discovered this when another service, Hudson, could not write to that directory. I want ...
18
votes
2answers
6k views

Automate the installation of postfix on Ubuntu

My system configuration script does an "apt-get install -y postfix". Unfortunately the script is halted when the postfix installer displays a configuration screen. Is there a method to force postfix ...
11
votes
2answers
11k views

How do I set default permissions for SFTP for an Ubuntu Server?

We have an Ubuntu 10.04 server. How can I set it so that new files created (or copied) over SFTP or SSH have g+rw and g+rwx permissions (where appropriate)? I'm also using setgid (chmod g+s) so that ...
11
votes
2answers
14k views

How to divert traffic based on hostname using HAProxy?

I've had some initial success with HAProxy setting up a bunch of app servers listening on various other ports. I now have another webserver listening on one port, and i'd like to what changes to make ...
3
votes
7answers
17k views

How to setup equivalent USVIDEO.ORG DNS-Proxy on Linux

I have a VPS in the USA running Ubuntu. I want to setup something similar to http://www.usvideo.org Basically, USVIDEO is a DNS service that allows Canadians to access American content like Hulu, ...
25
votes
7answers
22k views

Unzipping files that are flying in through a pipe

Can I make unzip or any similar programs work on the standard output? The situation is I'm downloading a zip file, which is supposed to be unzipped on the fly. Related issue: ...
7
votes
6answers
3k views

/var is using 91.4% of 3.99GB in new Ubuntu dedicated server from 1and1

Yesterday I purchased a dedicated server package from 1and1. I installed Rails, Mongo and nginx. Today, when I logged in, it displays this message: Welcome to Ubuntu 12.04 LTS (GNU/Linux ...
5
votes
2answers
6k views

Backup of KVM guests when using qcow2 disk files

I got a Ubuntu (hardy) system used for virtualization using KVM. Each guest got it's own qcow2 file used as disk. Guests are running Ubuntu (hardy). What would a good backup strategy be for such a ...
4
votes
4answers
9k views

Is adding the Debian repository to my apt source.list dangerous on Ubuntu? [closed]

I'm trying to install a package from a Debian repository. I am trying to install manually with dpkg errors because of missing or incomplete dependencies. This got me wondering, is it a mistake to just ...
3
votes
1answer
3k views

Trying to get SSH with public key (no password) + google authenticator working on Ubuntu 14.04.1

I'm using Ubuntu 14.04.1 (with OpenSSH 6.6 and libpam-google-authenticator 20130529-2). I'm trying to set up SSH logins where the public key authenticates (without a password) and a user is prompted ...
14
votes
2answers
8k views

Directory in /var/run gets deleted after hard reboot

I keep my sphinx pid in /var/run/sphinx/searchd.pid but every time I hard reboot the directory /var/run/sphinx disappears and sphinx fails to start. Is there a way to make that directory stick or ...
13
votes
3answers
26k views

Apache “Client denied by server configuration”, despite allowing access to directory (vhost configuration)

in Apache on Ubuntu I've set up a vhost, but in the browser I keep getting a "403 Access forbidden" error; the log says "Client denied by server configuration: /home/remix/". Looking for the solution ...
12
votes
4answers
8k 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?
12
votes
3answers
6k views

Set up sftp to use password but ssh not to use password

Is it possible to set up a user on ubuntu with openssh so that ssh does not use password authentication but sftp does? I assume that if I change /etc/ssh/ssh_config to have PasswordAuthentication yes ...
10
votes
6answers
1k views

How to choose a cloud service for backups

I am thinking of using a cloud service to backup one of my client's website. My (clients) main concerns are (in decreasing order of importance) Protection of IP (trade secrets, source code), user ...
9
votes
2answers
8k views

SSH Connections freezing with “Write failed: Broken pipe”

I am connecting to a CentOS 5.5 box via SSH from a Ubuntu 11.04 machine. The connection appears to work as expected when it is in active use (i.e. no lag or loss), but if it is left inactive for a ...
9
votes
1answer
11k views

How to generate a /etc/shadow compatible password for Ubuntu 10.04?

How are passwords generated that are used by Ubuntu 10.04? I know that they use SHA 512 as hashing algorithm, but I figure that there is some sort of salting done. I need to generate such a password ...
7
votes
2answers
2k views

How to create a “terminal server server” in xubuntu

I am pretty new to system administration, and I am definitively new to serverfault, so apologies should my question not be following SF standards to the 100%. This is my problem: I have a xubuntu ...
3
votes
11answers
861 views

Ubuntu Server SSH

I have a server with ubuntu. I do work on it over SSH. I had a problem with brute force attempts over port 22. I changed the port and I assumed it fixed the brute force problem. Am I right or are the ...
26
votes
4answers
19k views

How to disconnect from lxc-console

I'm working with lxc in Ubuntu 12.04, and it's really great. However, I am unable to disconnect from a lxc-console session after I've connected. I read somewhere that Ctrl-aq will disconnect me from ...
17
votes
4answers
7k 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 ...
16
votes
4answers
25k views

How to force downgrade of packages on Ubuntu (Karmic)?

After doing an update on a bunch of pulseaudio packages my microphone stopped working. It's fine, after all Karmic is still in Alpha. I have reported the bug to launchpad. In the meanwhile I would ...
14
votes
6answers
2k views

How to grant temporary access to server?

I've hired a remote consultant to tune up my servers. Now, I am not 100% confident about giving him root password and allow him to do whatever he wants to do on the servers. Ideally, I want to see ...
12
votes
8answers
11k views

Should I completely turn off swap for linux webserver?

Recently my friend told me that it is a good idea to turn off swap on linux webservers with enough memory. My server has 12 GB and currently uses 4GB (not counting cache and buffers) under peak load. ...
12
votes
7answers
27k views

df says disk is full, but it is not

On a virtualized server running Ubuntu 10.04, df reports the following: # df -h Filesystem Size Used Avail Use% Mounted on /dev/sda1 7.4G 7.0G 0 100% / none ...
11
votes
3answers
8k views

Can't create symlinks in virtualbox shared folders [closed]

A few days ago I found I can no longer create symlinks from Ubuntu in any directories that are shared with the OS X host. ln: creating symbolic link `foo': Read-only file system I'm able to create ...
11
votes
2answers
15k views

How do I get rsyslogd to log a server's FQDN instead of it's short hostname?

I'm trying to implement a simple centralized syslog server using stock rsyslogd (4.2.0-2ubuntu8.1) on Ubuntu 10.04 LTS. At this point I have all my client nodes sending logs to the central server, but ...
11
votes
2answers
7k views

PXE Booting Virtualbox guests in internal networking mode?

I am not sure if this is just specific to my distro's packages or is a vbox limitation. So, any help would be appreciated. Ok, so I have a network of VMs, with one VM acting as a NAT for the other ...
11
votes
6answers
25k views

Checkpoint VPN Linux Client

Is there a Linux client for Checkpoint VPN? Preferably for Ubuntu? -- Rubem
10
votes
2answers
5k views

Run command as Linux “system” user (shell = /bin/false)

I created a "system" user in Ubuntu 11.04 (adduser --system) for running certain cron jobs, but sometimes I want to test things out by manually running commands as that user. What's the easiest way to ...
5
votes
7answers
12k views

How to disable CD-ROM and USB for normal users in Linux?

How can access to CD-ROM and USB be disabled for normal users in Linux? As a part of security policy we need to disable CD-ROM and USB access for normal users. Only root users should have the access. ...
4
votes
3answers
5k views

Error when installing rabbitMQ server on Ubuntu 10.10

When I install rabbitMQ in synaptic via the following command sudo apt-get install rabbitmq-server it returns an error: Starting rabbitmq-server: FAILED - check /var/log/rabbitmq/startup_log, _err ...