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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18
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3answers
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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
18
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4answers
14k views

how to rename a VM using libvirt+KVM

How can I rename a VM on KVM+libvirt? I would like it to change the name in the 'inventory' as well as change the name of the storage etc.
18
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5answers
4k views

How to make upstart back off, rather than give up

I want Upstart to do two things: stop trying to respawn a failed process so fast never give up trying to respawn In an ideal world, upstart would try to restart a dead process after 1s, then ...
18
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3answers
25k views

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. ...
18
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6answers
15k views

Default groups assigned to the first user in Ubuntu Server 8.04?

I just made a silly mistake on my Ubuntu Server box: I added myself to a group using usermod -G, after which I discovered the -a option... The result is that I am now out of the admin group, and ...
17
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19answers
4k views

Why does redhat seem to be so popular in the enterprise world? [closed]

Title says it all. For personal usage, I tend to prefer Debian/Ubuntu over Redhat. It's not necessarily that I dislike Redhat (or more specifically CentOS or Fedora) so much as it is that I like ...
17
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17answers
63k views

Shell Command for Getting IP Address?

Is there a bash command to find the IP address for an Ubuntu box? I need to find the IP address so I can ssh into the machine later.
17
votes
6answers
25k views

How do I pipe a downloaded file to standard output in bash?

How is it possible to pipe out wget's downloaded file? If not what alternatives should I use?
17
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4answers
37k views

How do I request a new IP address from my DHCP server using Ubuntu Server?

I know there is a simple command for this, but how do I tell my Ubuntu server instance to request a new IP address from the DHCP server on eth0?
17
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4answers
2k views

What is NTP dispersion and how do I control it?

We roll out Ubuntu 14.04 servers on isolated networks, running ntpd 4.2.6p5, configured to use multiple NTP servers as provided by customers (no access to pool.ntp.org). Our dumb terminal client ...
17
votes
3answers
113k views

How to write ISO image to usb memory stick from linux command-line?

I'm having trouble figuring out how I would write an ISO disk image to a USB flash memory device from the command line in Ubuntu. I have the Startup Disk Creator utility, but I need to be able to ...
17
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4answers
13k views

How to get HTTP preseed to work correctly on Ubuntu 10.04 LTS (Lucid)?

Installation media: ubuntu-10.04-desktop-i386.iso I tried a lot of different boot parameters, but either the installer ignored the preseed configuration, or it boot itself directly as LiveCD. An ...
17
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1answer
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what s+ S1+ T R+ mean in ps ax ps list

I run this command and got result this but not able to understand the result which node instance should i kill ps ax | grep node 23308 pts/3 S+ 0:00 sudo node index.js 23310 pts/3 Sl+ ...
17
votes
1answer
22k views

How to configure Tomcat to only listen to 127.0.0.1?

The environment is Ubuntu 10.04.1 LTS running Tomcat 6 and Apache 2.2 from the repos. Apache is configured to proxy requests to Tomcat, so I really want to turn off Tomcat listening to requests on ...
17
votes
4answers
10k views

Ubuntu/Debian: Show list of available versions of a specific package

How can I list all available versions of specific package? I know with apt-get install myPackage=1.2.3 a specific version could be installed. And with apt-show-versions -a myPackage I would ...
17
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6answers
6k 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 ...
17
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3answers
9k views

On Ubuntu 10.04, should /etc/hostname contain the server's FQDN?

On Ubuntu 10.04, should /etc/hostname contain the server's fully-qualified domain name?
17
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3answers
22k views

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 ...
17
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3answers
20k views

How can I install Apache with a specific version?

Because of Ubuntu updating, I made the mistake to upgrade Apache 2.2 to 2.4—many things went wrong. I have no idea how to specify the version after apt-get remove apache2. apt-get install apache2 ...
17
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1answer
8k views

Can I have two versions of the same package in an apt repository?

I'm running Ubuntu 10.04 across my entire environment. To make code deploys easier, we are implementing a private apt repository where we can deploy builds of our code. One of the requirements of ...
17
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7answers
17k views

Can cron write job output to a log *by default* (instead of mail)?

We all know the right way to handle output from cron jobs is to redirect it to a file: 0 * * * * /bin/date >> /var/log/date.log 2>&1 However, sometimes admins are lazy, forgetful, or ...
17
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1answer
1k views

Using Avahi on DreamPlug Ubuntu with iPads

I have the following very peculiar issue with using Avahi on the DreamPlug (which is a plug computer running Ubuntu Jaunty). After spending days on this, I think I've managed to narrow down the issue....
16
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6answers
15k views

Active Directory vs OpenLDAP

This is for a small company (12 developers) who haven't implemented any centralized user database - they've grown organically and just created accounts on computers as they needed. From a management ...
16
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4answers
25k views

Unable to install mysql-server in Ubuntu

I am unable to install mysql-server on my ubuntu 9.10 server machine. When using apt-get install mysql-server the output is : # apt-get install mysql-server Reading package lists... Done Building ...
16
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3answers
5k views

Alternatives to apache benchmark? [closed]

I'd like some tools for ubuntu that I can use to test my server, how much it can handle. Any suggestions? I've used apache benchmark before, but I'd like to try out something else. (As a side ...
16
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4answers
20k 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 ...
16
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2answers
10k 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 ...
16
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1answer
26k views
16
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2answers
8k 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 ...
16
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3answers
27k views

How to configure Apache (sites-available vs httpd.conf)

I've been trying to follow a few basic tutorials explaining how to get Apache up and running (on ubuntu, running on Amazon). I've mostly come up blank, because all the tutorials told me to configure ...
16
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7answers
23k views

How to remotely install Linux via SSH?

I need to remotely install Ubuntu Server 10.04 (x86) on a server currently running RHEL 3.4 (x86). I'll have to be very careful because no one can press the restart button for me if anything goes ...
16
votes
6answers
15k 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 ...
16
votes
1answer
10k views

php-mysqlnd or php-mysql

Long story short: just installed Ubuntu 12.04 (Debian based), nginx, php-fpm and mysql. Now I need the MySQL driver for PHP, but which should I choose? Which is better php-mysqlnd or php-mysql?
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3answers
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what is sensible-mda and do i need it?

I'm running Ubuntu Intrepid, and have been seeing the following my logs: Aug 23 16:01:03 wp1 sm-mta[13700]: n7NFJIad013566: Warning: program /usr/sbin/sensible-mda unsafe: No such file or directory ...
16
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3answers
19k views

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 ...
16
votes
3answers
41k views

Soft limit vs Hard limit?

Can anyone explain in layman's terms what the difference between soft and hard limit is? Should I set my soft and hard limit to be the same? Or should soft be significantly lower? Does the system ...
16
votes
4answers
6k views

max files per directory in ext4

I manage an application that contains a filestore in which all the files are stored with the filenames equal to their md5 sums. All files are stored in one directory. Currently there are thousands, ...
16
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5answers
28k views

Dovecot vs Courier vs Cyrus [closed]

What is best for a Personal/SMB mail server running on an Ubuntu Server (8.04+)? I want to setup my own mail server at home to evaluate some options for my company before I make a recommendation. ...
16
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4answers
26k 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 ...
16
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4answers
15k views

Booting a native Windows install in Virtualbox: is it possible? [closed]

I am looking for something similiar to Bootcamp. Currently, I run Ubuntu Maveric as my primary operating system and run Windows 7 in Virtualbox. For some tasks, however, running Windows virtualized ...
16
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4answers
3k views

Is there an open source email client that will work with Exchange 2007?

Recently I've been playing around with Ubuntu 9.04 on one of my work systems. The only real bump in the road that keeps it from being being used as my main workstation is that I cannot find a ...
16
votes
3answers
14k views

Open source alternative for Canonical Landscape? [closed]

From Canonical: Landscape is an easy-to-use systems management and monitoring service that enables you to manage multiple Ubuntu machines as easily as one through a simple Web-based ...
15
votes
4answers
12k 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?
15
votes
6answers
50k views

how to auto start openvpn (client) on ubuntu 12.04 cli?

I have an *.ovpn file that works if I type in sudo openvpn client.ovpn Now I would like to start up openvpn when I boot the computer. It's a headless version of ubuntu - if that matters - 12.04 ...
15
votes
2answers
13k 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?
15
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3answers
49k views

How to setup a MySql server to accept remote connections?

I am installing a MySql server in Ubuntu desktop. I could connect MySql Query Browser to it when specifying the Server Hostname as localhost, but when I replace it by the machine's IP it stops working ...
15
votes
7answers
27k views

Out of disk space, what's the source?

Filesystem Size Used Avail Use% Mounted on /dev/sda1 220G 220G 0 100% / none 1.9G 168K 1.9G 1% /dev none 1.9G 0 1.9G 0% /dev/...
15
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3answers
22k views

How to get - number of threads per process?

This is one Ubuntu 9.10 server. Also how to see memory usage per process? Thanks
15
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5answers
16k views

Recover from shutdown during Ubuntu distribution upgrade

I have a computer which was unexpectedly shut down during a distribution upgrade (Ubuntu 8.10 -> 9.04). It now won't finish booting - various X errors, then it goes to the login screen but won't ...
15
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3answers
16k views

Do I need to refresh or restart anything after I add/update a crontab in Ubuntu Server 8.04?

When you change something in Apache you need to reload or restart apache. Does anything need to be refreshed or restarted in Ubuntu Server 8.04 after I add/update the crontab? Thanks a bunch for your ...