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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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 ...
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6answers
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How to force MySQL to connect by TCP instead of a Unix socket?

I would like to analyze mysql traffic. Right now, all mysql requests are sent to the MySQL unix socket: unix 2 [ ACC ] STREAM LISTENING 3734388 15304/mysqld ...
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6answers
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SSD for swap on Ubuntu server

Currently I am reading SSD reviews and I wonder how much exactly I will benefit if I move the 24 GB swap from 7200rpm HDD to SSD. Does anyone implemented swap space on SSD? Is this generally good ...
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8answers
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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. ...
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How can I find the biggest directories in unix / Ubuntu?

Is there a way in Unix to see the biggest directories on disk ? I need to know why I'm almost done with the space on the server, and I dunno where most of the space is used.. thanks
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How do you swap the caps lock to control in xfce?

I used to have the caps lock and control swapped in GNOME, but when I upgraded to Ubuntu 9.04 I also changed my desktop environment to Xfce. I have the following line in my xorg.conf: Option ...
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2answers
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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 ...
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4answers
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Effective way to ensure “clean slate system” for continuous integration service

We want to set up a continuous integration (CI) service for our project. That CI service should control all aspects of the project life, including deployment. That is, we want a CI agent at each ...
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5answers
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Tips to gracefully take over a (UNIX) production server

After months of neglect, e-mail flames and management battles our current sysadmin was fired and handed over "the server credentials" to me. Such credentials consist in a root password and nothing ...
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6answers
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pam service(sshd) ignoring max retries

I have vps that I use to run a webserver on, it currently runs ubuntu server 12.04. Since a few weeks I keep getting a lot of errors in my ssh console. 2014 Apr 11 08:41:18 vps847 PAM service(sshd) ...
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3answers
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Why is Apache running so many processes? Excessive RAM here?

I notice Apache is running multiple processes on my LAMP server (ubuntu 10.10). I'm just running a Wordpress site with MySQL as a database. It seems like www-data is running apache2 more than it ...
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2answers
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Installing imagick PHP extension on Ubuntu

I'm trying to install the imagick pecl extension on my Ubuntu server and am getting the below error. I've installed the ImageMagick rpm using aptitude already and the pecl extension is version 2.3.0. ...
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Check incoming network traffic in real time?

Is there a way I can monitor incoming network traffic in real time on my server? Preferably in terms of *bps Running Ubuntu
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How to setup etckeeper with Mercurial in Ubuntu?

I'm interested in installing etckeeper with Mercurial in my Ubuntu system. My reason is that I don't know how to use Git and don't want to learn at the moment. If I check the package description it ...
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4answers
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simple postfix configuration - forward all incoming email to single address

I've a Ubuntu 9.04 server installation which is hosting a small number of websites (currently two, and will remain in single figures). The email requirements for the server are very limited - to ...
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2answers
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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 ...
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mount.nfs: access denied by server while mounting

On my Ubuntu system, I have this line in /etc/fstab: myserver:/home/me /mnt/me nfs rsize=8192,wsize=8192,timeo=14,intr When I do sudo mount -a I get: mount.nfs: access denied by server while ...
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Should the virtualization host be allowed to run any service?

I recently setup a virtualization server for the small company I'm running. This server runs few virtual machines that are used for development, testing, etc... My business partner works from a ...
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Ubuntu Server message says packages can be updated, but apt-get does not update any [duplicate]

Possible Duplicate: updates in amazon-ec2 ubuntu 10.04 server When I log into an Ubuntu 10.04.2 LTS server, I see the message: 42 packages can be updated. 18 updates are security updates. ...
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3answers
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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 ...
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6answers
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Checkpoint VPN Linux Client

Is there a Linux client for Checkpoint VPN? Preferably for Ubuntu? -- Rubem
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3answers
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Restricting account logins using LDAP and PAM

I was hoping some PAM/LDAP gurus may be able to help me out here. I've recently set up an LDAP directory on Ubuntu Server to hold accounts for both my clients (for use with web-based systems) and ...
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2answers
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What are the steps to make the php mail() function work on ubuntu-server?

I want to enable the simple php mail() function on an Ubuntu server. This will only be used for sending administration stuff and logs. This is all the mail functionality that I want on this machine. ...
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Starting network connection from Ubuntu recovery?

I tried to upgrade Ubuntu from Hardy to Intrepid last night, and seem to have killed it. I can boot into "recovery mode" and the root shell, but it freezes when it tries to start the Gnome ...
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My linux server was hacked. How do I find out how and when it was done?

I have a home server running a desktop ubuntu distribution. I found this in my crontab * * * * * /home/username/ /.access.log/y2kupdate >/dev/null 2>&1 and when looking in that directory ...
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What's the cause of high LOC interrupts?

I'm seeing huge spikes in LOC interrupts - around 4 million per second, what exactly is the LOC interrupt, what would cause these spikes, and what can I do about it? Here's a munin graph illustrating ...
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Why can't I ssh into (or even ping) my Ubuntu VM from the Mac OS X host?

I'm running Ubuntu 8.04 as a virtual machine using VMware Fusion 3.0 on Mac OS X 10.5.8. I want to be able to ssh into my VM from the Mac OS X host (so I can use MacFUSE and SSHFS to mount the VM's ...
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1answer
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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 ...
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2answers
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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 ...
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1answer
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I am still running Ubuntu 13.04, how should I react to the Heartbleed Bug? [duplicate]

I know that 13.04 is affected (or at least my installation is) because of the OpenSSL version currently installed. However, after running sudo apt-get update sudo apt-get upgrade I checked my ...
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2answers
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SSH session never closes when executing “apt-get install”

Problem When running apt-get install in an SSH session, the session never closes. Example: ssh user@target "sudo apt-get -y install my_package" The my_package does get installed properly, but the ...
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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 ...
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Why is /dev/urandom only readable by root since Ubuntu 12.04 and how can I “fix” it?

I used to work with Ubuntu 10.04 templates on a lot of servers. Since changing to 12.04 I have problems that I've now isolated. The /dev/urandom device is only accessible to root. This caused SSL ...
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5answers
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Out of nowhere, ssh_exchange_identification: Connection closed by remote host

I am running Ubuntu 10.10 on a remote box. I ssh to it everyday without issues but today out of the blue, I get the following error: ssh_exchange_identification: Connection closed by remote host If ...
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11answers
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Any way to run Linux as a Virtual Machine on top of Windows so can have best of both worlds?

Since Linux has a lot of useful tools, while Windows has a lot of apps (like Chrome), instead of buying another machine to run Linux, is there a way to run it as a Virtual Machine on the PC? The ...
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4answers
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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 ...
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Can Ubuntu Desktop “become” Ubuntu Server?

Am I correct that Ubuntu desktop and server are the same os but that desktop runs X and lacks things that a server might have like dhcp server, mysqld, apache, etc.? And that if I add those items it ...
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GUI on Ubuntu server?

I'm primarily a developer, but as part of this I'm running an Ubuntu server for a client where he has several small to medium sized websites. Although my main development environment has generally ...
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3answers
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Inherit existing server

I have just inherited 6 web servers from previous server guy who was fired, I am not a sysadmin I am more a DevOps. Could anyone point me to some sort of standard checklist one would follow when ...
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How to convert 'dmesg' time format to 'real' time format

I have (for example) this log entry in dmesg output: [600711.395348] do_trap: 6 callbacks suppressed Is there a possibility to convert this 'dmesg' time to 'real' time to know, when this event ...
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5answers
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How can I manage apt efficiently on multiple machines?

I manage around 30 Ubuntu servers using puppet. I've seen many references to cron-apt and apticron as approaches to keeping their packages up to date but I haven't been able to find a way to ...
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3answers
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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 ...
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4answers
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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?
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2answers
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Why is ssh agent forwarding not working?

In my own computer, running MacOSX, I have this in ~/.ssh/config Host * ForwardAgent yes Host b1 ForwardAgent yes b1 is a virtual machine running Ubuntu 12.04. I ssh to it like this: ssh pupeno@b1 ...
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2answers
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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 ...
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How do I find the cause for a huge difference in performance between two identical Ubuntu servers?

I am running two Dell R410 servers in the same rack of a data center (behind a load balancer). Both have the same hardware configuration, run Ubuntu 10.4, have the same packages installed and run the ...
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Why is ntpd not updating the time on my server?

I have ntpd running on my server. It's all the default settings, except I commented out its ability to be a server to other machines: # restrict -4 default kod notrap nomodify nopeer noquery ...
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1answer
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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 ...
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2answers
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synergy2 replacement

Anyone know of a good replacement for Synergy2 that is cross platform and open source? I've been looking around since I upgraded to Win7 which Synergy2 doesn't play well with - which doesn't surprise ...
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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 ...