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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4answers
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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 ...
13
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3answers
532 views

Which method to use for granting sudo

What is the difference between adding a user to /etc/sudoers and usermod -a -G sudo? Which method should be used for granting sudo?
13
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4answers
10k 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?
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5answers
15k 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 ...
13
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5answers
3k views

Fixing services that have been disabled in /etc/default/ with puppet?

I'm using puppet to (theoretically) get npcd to start upon installation, however on Ubuntu, that service comes installed with the default setting in /etc/default/npcd of RUN="no": $ cat ...
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4answers
10k views

What is vmlinuz and why do I care?

I just got a network alert that I've never seen before, on one of the few Ubuntu boxes that we have: The following monitoring trigger has been fired: /vmlinuz has been changed on server XXXXX: ...
13
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3answers
31k views

Ubuntu 10.04/CURL: How do I fix/update the CA Bundle?

I recently upgraded our server from 8.04 to 10.04, and all the software along with it. From what I've found online, it seems that the new version of CURL doesn't include a CA bundle, and, as a ...
13
votes
2answers
7k 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 ...
13
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3answers
36k 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 ...
13
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6answers
32k views

Checkpoint VPN Linux Client

Is there a Linux client for Checkpoint VPN? Preferably for Ubuntu?
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5answers
13k views

How can I configure unattended installation of Ubuntu?

I'd like to configure an installer for Ubuntu which runs in 'unattended' mode and answers all the questions with defaults or pre-configured settings. Ideally it should run and reboot on it's own, ...
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7answers
8k views

How to view all ssl certificates in a bundle?

I have a certificate bundle .crt file. doing openssl x509 -in bundle.crt -text -noout only shows the root certificate. how do i see all the other certificates?
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4answers
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How to fix “BUG: soft lockup - CPU#0 stuck for 17163091968s”?

UPDATE: I updated the title of the message, because I've recently seen more of these problems with this exact time amount of 17163091968s. This should help people investigating the symptoms to find ...
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3answers
8k 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 ...
13
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5answers
144 views

ubuntu servers - what do i need to do to keep it uptodate

I am setting up an ubuntu server and want to know what I should be doing on it regularly. apt-get update/upgrade seems obvious. Is there a glsa check for example? Anything else I should be running? ...
13
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4answers
14k views

How can I configure a private (friends only) IRC Server?

I am trying to setup an IRC server on my machine for a bunch of friends and me to use. This is an ubuntu box and I have installed dancer-ircd and dancer-services and gotten everything up and running ...
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20answers
1k views

Are there any reasons NOT to run an Ubuntu server?

I'm going to be setting up a network for a small office soon. The network will consist of about 5 workstations (soon to be more) and 2-3 servers (one "real" server and a couple ...
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11answers
7k views

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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3answers
3k views

How to make folders 00-99 with a single command in Ubuntu?

I need to create folders starting from 00 to 99 (00, 01, 02, 03, etc....) in several hundred places. Is there a single line command that will let me do that?
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3answers
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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 ...
12
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3answers
870 views

grep behaving differently on Fedora vs Ubuntu

So when I run this in Fedora I'm seeing this: $ ls hmm_data/indivA12_AATAAG/refs/par1/ 2R-orths.alleles 2R-ref.alleles $ ls hmm_data/indivA12_AATAAG/refs/par1/ | grep -F '-ref.alleles' ...
12
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3answers
10k 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 ...
12
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4answers
36k views

Deleting All Partitions From the Command Line

How do you delete all partitions on a device from the command line on Linux (specifically Ubuntu)? I tried looking at fdisk, but it presents an interactive prompt. I'm looking for a single command, ...
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4answers
11k views

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
18k 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 ...
12
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2answers
15k views

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. ...
12
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4answers
18k 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 ...
12
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4answers
6k views

Ubuntu's garbage collection cron job for PHP sessions takes 25 minutes to run, why?

Ubuntu has a cron job set up which looks for and deletes old PHP sessions: # Look for and purge old sessions every 30 minutes 09,39 * * * * root [ -x /usr/lib/php5/maxlifetime ] \ ...
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2answers
2k views

ubuntu 10.10 sshd contains “YOU WANNA SMOKE A SPLIFF” and pot leaf ascii art. Does this mean I've been hacked?

My sshd binary on an ubuntu 10.10 machine contains the following ascii artwork: ng: %.100sToo many lines in environment file %sUser %.100s not allowed because %s exists YOU WANNA . ...
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11answers
9k views

What creates CPU I/O wait but no disk operations?

I have CPU I/O wait steady around 50%, but when I run iostat 1 it shows little to no disk activity. What causes wait without iops? NOTE: There no NFS or FUSE filesystems here, but it is using Xen ...
12
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3answers
13k 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 ...
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2answers
38k views

Install php extensions on ubuntu

I have a Ubuntu 9.10 server. I have installed apache2 and php5 using the apt-get commands. How does one install php extensions? Are there commands like apt-get to get them? Or should I manually look ...
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5answers
18k views

Apache: SSLCertificateKeyFile: file does not exist or is empty

I am configuring SSL for Apache 2. My system is Ubuntu Server 10.04 LTS. I have the following settings related to SSL in my vhost configuration: SSLEngine On SSLCertificateKeyFile ...
12
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1answer
7k 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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2answers
2k views

How safe are Unattended Upgrades/Automatic Updates for Ubuntu

I'm in the process of trying to keep several ubuntu box's up to date and patched (10.4.2 LTS), one suggestion I've been getting is setting up unattended upgrades ...
12
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1answer
13k views

Why does this ldapadd command quit with an “Invalid syntax” error?

I'm very new to openldap but extremely well versed in the linux/unix environment. I'm trying to setup my very first test openldap environment using the guide here. I've also read most of the admin ...
12
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3answers
4k views

NFS with encrypted ubuntu home directory

I am having trouble getting NFS setup on with vagrant: On my local machine I have installed NFS: apt-get install nfs-common nfs-kernel-server And in my Vagrantfile set it to be used: ...
12
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1answer
7k 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 ...
12
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2answers
8k 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 ...
12
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8answers
23k views

Command line program to test DHCP service

Is there a simple ping-like command to test whether a DHCP service is running on a network? ...on Linux
11
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3answers
12k 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 ...
11
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2answers
28k views

setting up a basic mod_proxy virtual host

I'm trying to set up a basic virtual host to proxy all requests to test.local to a WEBrick server I have running on 127.0.0.1:8080 while keeping all requests to localhost going to my static files in ...
11
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2answers
18k views

Turning off cp (copy) command's interactive mode (cp : overwrite ?)

Does anyone know how I would turn off the interactive mode when using cp? I am trying to copy a directory recursively into another and for each file that is getting overwritten I have to answer 'y'. ...
11
votes
4answers
3k views

Limit Apache to a single IP

I've got a server with a bunch of IP addresses, and I only want Apache listening on one of them. It doesn't sound like a hard thing to do, and I've done it once before a while ago, but I'm having some ...
11
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3answers
29k views

Can I scp a folder that has sub folders?

I have a folder that contains files for a static website like: /site/index.html /site/css/css.css /site/js/js.js /site/images/... If I update something on my laptop, I want a single command to send ...
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2answers
18k 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 ...
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5answers
756 views

Is it bad to have a very full hard drive on a high traffic database server?

Running an Ubuntu server with MySQL for a high traffic production database server. Nothing else is running on the machine except the MySQL instance. We store daily database backups on the DB server, ...
11
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2answers
16k views

Ubuntu ufw: set a rule on a per interface basis

I want to create a rule that allows anyone on eth1 to access port 80. Can UFW do this or should I go back to using Shorewall? To clarify: this is a capabilties question, can ufw handle interfaces as ...
11
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2answers
21k views

How to prevent squid from caching and just filter?

I have set a proxy server on my network. I only want to filter the web traffic. So, I have Squid as a proxy and Qlproxy as the filter : http://www.quintolabs.com/qlicap_info.php My server have only ...
11
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4answers
16k views

Failed tls handshake. Does not contain any IP SANs

I'm trying to set up logstash forwarder, but I have issues with making a proper secure channel. Trying to configure this with two ubuntu (server 14.04) machines running in virtualbox. They are 100% ...