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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51
votes
5answers
3k views

How should an IT department choose a Linux distribution: Technical reasons

There is a lot of community feeling about what Linux distributions are appropriate for production server environments and what aren't. Some of this is based on the availability of commercial support. ...
103
votes
17answers
130k views

CentOS vs. Ubuntu [closed]

I had a web server that ran Ubuntu, but the hard drive failed recently and everything was erased. I decided to try CentOS on the machine instead of Ubuntu, since it's based on Red Hat. That ...
20
votes
2answers
27k views

How to reduce number of sockets in TIME_WAIT?

Ubuntu Server 10.04.1 x86 I've got a machine with a FCGI HTTP service behind nginx, that serves a lot of small HTTP requests to a lot of different clients. (About 230 requests per second in the peak ...
10
votes
2answers
6k views

SSL site not using the correct IP in Apache and Ubuntu

I'm trying to set up an apache-ubuntu-php webserver. My webserver will host multiple SSL sites, each SSL site will have it's own IP address (unless there's a better way to do this). So I suppose the ...
4
votes
2answers
284 views

Accidential CHMOD 755

Alright, I accidentially chomdded everything to 755, which isn't as terrible as chowning everything to the local user. How insecure is this and how would I restore it easily, without reinstalling?
72
votes
7answers
28k views

Heartbleed: how to reliably and portably check the OpenSSL version?

I was looking at a reliable and portable way to check the OpenSSL version on GNU/Linux and other systems, so users can easily discover if they should upgrade their SSL because of the Heartbleed bug. ...
22
votes
8answers
4k views

accidently ran “chown www-data:www-data / -R” as root

i just ran this a few seconds ago, i managed to do ctrl-c as soon as i realized what i started doing. so far in the only dir its started going through is /bin im afraid to do anything else, so far ...
5
votes
1answer
2k views

How do I set permissions structure for multiple users editing multiple sites in /var/www on Ubuntu 9.10?

I'm setting up an Ubuntu server that will have 3 or 4 VirtualHosts that I want users to be able to work in (add new files, edit old files, etc.). I currently plan on storing the sites in /var/www but ...
35
votes
10answers
12k views

Securing a fresh Ubuntu server [closed]

Say I've got a fresh install of Ubuntu, what steps should I take to secure it for use as a Rails application server?
36
votes
4answers
14k views

Why don't EC2 ubuntu images have swap?

I started a couple servers on EC2 and they don't have swap. Am I doing something wrong or is it that the machines just don't have any?
18
votes
7answers
6k views

How to configure a shortcut for an SSH connection through a SSH tunnel

My company production servers (FOO, BAR...) are located behind two gateway servers (A, B). In order to connect to server FOO, I have to open a ssh connection with server A or B with my username ...
19
votes
6answers
11k views

Scripted install of MySQL on Ubuntu

I need to write a script that will build my server from a fresh Ubuntu server install. Among things like Apache and PHP it needs to install MySQL. The only problem here is that when I install MySQL ...
25
votes
7answers
2k views

Ubuntu, how to setup a new machine like an existing one

I have one machine setup with the apps I need, and I'd like to install the same on a new Ubuntu box. Is there a script that will list all the installed apps, so that I can diff between the boxes and ...
11
votes
3answers
31k views

Iptables: How to allow only one ip through specific port?

How can I on my ubuntu server, in Iptables only allow one IP adress on a specific port? Thanks
23
votes
2answers
10k 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 ...
6
votes
3answers
5k views

How to redirect all outgoing email from postfix to a single address for testing

I am setting up a testing server for a web based application that sends some email notifications. Sometimes testing is performed with real customer data, and for that reason I need to guarantee that ...
14
votes
4answers
15k views

upstart scripts: run a task after networking goes up

I'm working on moving my current server setup to newer hardware, and migrating from ubuntu karmic koala to lucid lynx. Currently i'm using gw6c (compiled from the gogo6 website, as opposed to the ...
9
votes
10answers
11k views

Which Distributed File System as a backend for Cloud Computing?

I have a basic cloud running on Ubuntu Server (9.04) and Eucalyptus. Walrus (Eucalyptus' API compatable S3 implementation) stores files by on the cloud controller. However each of the other 4 server ...
22
votes
1answer
7k views

How do I ask apt-get to skip any interactive post-install configuration steps?

I have a server build script which uses apt-get to install packages. It then puts pre-written configuration files directly in place, so the interactive post-install configuration dialog in packages ...
4
votes
5answers
8k views

What causes PHP pages to consistently download instead of running normally

I'm running a Ubuntu Server on a VM, to test out different web forum solutions. I have set up a ~/public_html/ to be accessible with the apache2 web server, and that works fine. However when I go to ...
25
votes
9answers
39k 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 ...
6
votes
2answers
2k views

My cron tasks report command not found [duplicate]

This is the contents of my crontab file: 0 0,6,12,18 * * * cd /var/www/app/current && backup perform --trigger db_backup --config_file config/backup.rb --data-path db --log-path log ...
5
votes
7answers
2k views

ubuntu server slowly filling up

We had our samba server (ubuntu 8.04 ltr) share fill up the other day but when I went to look at it I cant see any of the shares have to much on them we have 5 group shares and then each users has an ...
8
votes
7answers
2k views

Disable prompts while installing a Debian package

How can i disable totally the prompts that appear while installing a Debian package, i've used all the options that i've found but there are some packages that are still prompting. I'm using this ...
3
votes
5answers
2k views

Enable access without “www.” on Ubuntu

I want to enable the access to my site without the "www." prefix. I tried to insert this in my /etc/apache2/sites-available file: <VirtualHost *:80> serverName mydomain.gov.br ...
1
vote
5answers
423 views

What's needed for a complete backup system?

For my new server, I want to setup a proper backup solution. I've found a great setup that will do twice-daily incremental backups via Dropbox. I plan on backing up my various databases, the webroot ...
5
votes
1answer
1k views

Encrypted LVM on RAID1 - Failure testing, manual mount

We have an Ubuntu 10.04 LTS server set up with LVM running on top of disk encryption, which runs on top of a RAID1 volume comprised of two physical SATA disks. The configuration looks like this: ...
1
vote
1answer
43 views

Creating new users using PHP not recognized by Apache 2.4

I have a server setup where new linux users are created using (PHP) shell_exec ( '/usr/sbin/useradd ' . $username ); exec ('usermod -a -G ' . $username . ' '. $username); #add user into the usergroup ...
1
vote
2answers
106 views

Cant find my harddrives in ubuntu installation?

I was trying to setup a Microserver with two 1TB harddrives as a software RAID. Somehow it didnt work and now ubuntu 14.04 is not starting. My problem is that I dont see the drives anymore when I go ...
32
votes
4answers
50k views

how do I upgrade from php 5.3 to php 5.4.6 in ubuntu?

Is there an easy way out to get the latest PHP? I have tried updating my package but none of it has 5.4.6 yet.. if anyone knows on how to do it quickly, can it be shared here? I've tried compiling ...
16
votes
6answers
13k views

How to Setup Ubuntu Mail Server with Google Apps?

I have a domain, let's call it foobar.com. All of the MX records for foobar.com point to Google's mail servers because I am using Google Apps for your domain to manage it. It's great because everyone ...
44
votes
10answers
174k views

How to start/stop iptables on Ubuntu?

How can I start/stop the iptables service on Ubuntu? I have tried service iptables stop but it is giving "unrecognized service". Why is it doing so? Is there any other method?
13
votes
3answers
25k views

MySQL: How do I get my “Maximum possible memory usage” down?

I've recently been having problems with thrashing as a result of running out of memory. (My VPS has 256M total) I'm trying to tune MySQL using mysqltuner.pl, and get the following results: -------- ...
28
votes
4answers
36k views

Setup ubuntu server to send mail()

I tried searching a lot but unable to find how to actually setup a ubuntu server, so that I can send mails through php using mail() function in php. I have apache2, mysql and php5 installed on my ...
22
votes
7answers
32k views

How to set up Mod_WSGI for Python on Ubuntu

I am trying to setup MOD_WSGI on my Ubuntu box. I have found steps that said I needed to do the following steps I found at http://ubuntuforums.org/showthread.php?t=833766 sudo apt-get install ...
10
votes
2answers
10k views

How can I block all but three ports in Ubuntu?

How can I block all ports except for 1962, 999, 12020? One port for SSH and two others for a kind of script. So, it's necessary to allow outgoing on these ports, right? My iptables: # Generated by ...
13
votes
2answers
2k views

What is the difference between sudo -i and sudo su -

What is the difference between commands sudo -i and sudo su -? Are they the same?
5
votes
3answers
9k views

How to setup Apache NameVirtualHost on SSL?

I would like to set the A record of two DNS to point to my Ubuntu intance. Apache should then read the domain name accordingly and point the incoming request to the right physical path. I have set ...
25
votes
8answers
17k views

My server is still vulnerable to heartbleed even after I update OpenSSL

I have an Ubuntu 12.04 server. I have updated the OpenSSL package in order to fix the heartbleed vulnerability. But I am still vulnerable even, even though I have restarted the web server, and even ...
6
votes
13answers
7k views

Ubuntu server 9.10 freezes up after ~10 minutes

I just upgraded my Ubuntu server from 9.04 to 9.10 and after about 10 minutes it locks up. It won't respond to ping, can't ssh in and the terminal doesn't accept keyboard input. It does not have X ...
6
votes
4answers
2k views

Record everything on command line centos /fedora/ ubuntu

we are 100% Linux user across the network and we do work round clock, what happens shift change next admin come to his shift on that time what all issues comes he get resolve the issues but they just ...
4
votes
1answer
2k views

How can I monitor bandwidth usage by Virtual Host in Apache on Ubuntu

My Environment: Apache 2.2.9, Ubuntu 8.10 I am trying to find a way to monitor the bandwidth usage on my server broken out by each virtualhost WITHOUT installing something like PLESK, CPanel, or ...
8
votes
2answers
4k views

hosts file seems to be ignored

I have almost fresh Ubuntu desktop box. OS was installed two weeks ago and updated from karmic repositories. Last week I had no problems with DNS. But this week something had changed. I'm not sure ...
4
votes
2answers
5k views

fsck root filesystem on a remote machine

I have filesystem problems on a machine running Ubuntu 8.04 machine in a colocation facility. What was once a directory now looks like this: b--xr-SrwT 52 825452087 876163170 56, 97 2021-10-10 05:43 ...
4
votes
3answers
5k views

Add email account to postfix

I have add a user in linux called "mailer". I'm only using this user to send outgoing mail, not receive. What do I need to do in order use the following SMTP information to send outgoing mail? ...
9
votes
1answer
5k views

open file descriptor limits.conf setting isn't read by ulimit even when pam_limits.so is required

I am trying to raise the open file descriptor maximum for all users on an ubuntu machine. I've added the following lines to /etc/security/limits.conf: * soft nofile 100000 ...
6
votes
5answers
1k views

MySQL stopped working - full disk

Maybe it is because I am lacking in free disk space, take a look: Filesystem Size Used Avail Use% Mounted on /dev/sda2 1.9G 208M 1.6G 12% / none 998M 192K ...
4
votes
1answer
672 views

Undoing chmod 777

Sometimes in desperation, to test if my problem is not the permission problem I do: sudo chmod -R 777 mydir/ In most cases it does not helps, and now I have two problems ;) Files inside mydir/ had ...
3
votes
2answers
2k views

Upgrading Ubuntu Server

I tried to upgrade my Ubuntu Server following these instructions: http://www.ubuntu.com/desktop/get-ubuntu/upgrade But the command do-release-upgrade (as root) brings me: Checking for a new ubuntu ...
3
votes
2answers
3k views

root directory permissions changed to 777 by mistake whats now?

By Mistake on Ubuntu 9.04 my colleague has changed the permissions to 777 on root directory (/) whats the best way to recover the permissions ?