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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Putting /etc under source control

I would like to put my /etc directory iunder source control using bazaar. Are there any gotchas in doing this. It seems safer to do it user an ordinary user rather than root - might there a be a ...
14
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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 ...
14
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2answers
6k views

Where is initdb in Ubuntu

I want to reset my postgresql database back to its initial condition after install. Apparently initdb is the way to do this, but although the command has a man page, it doesn't seem to be anywhere on ...
14
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4answers
18k 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 ...
14
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3answers
12k views

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 ...
14
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5answers
22k 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. ...
14
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3answers
29k 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: -------- ...
14
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2answers
5k views

How can I get Jenkins to stop listening for remote connections?

I have Jenkins sitting behind Nginx, with Nginx taking care of authentication, but Jenkins is still listening on port 8080 externally, so by accessing the box on port 8080 people can bypass Nginx. ...
14
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5answers
28k 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 ...
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6answers
10k views

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) ...
13
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3answers
521 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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3answers
21k 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 ...
13
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3answers
37k 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
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4answers
18k views

How to run script via SSH that doesn't end when I close connection?

I need to run script, that takes long time to execute, or I just want it to run forever. I can't just SSH to my machine, because when I disconnect it stops running. Is there any way to run script ...
13
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5answers
2k 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 ...
13
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4answers
9k 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.
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5answers
36k views

console-kit-daemon - can it be stopped?

I have 60 instances of Console Kit daemon on Ubuntu 9.04 server installation. Is it safe to kill those or stop these processes. They seem to be taking about 20% of RAM each(see on htop).
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2answers
3k views

Why does Debian clean php sessions with a cron job instead of using php's built-in garbage collector?

Debian and derivatives (Ubuntu) don't use the php session garbage collector session.gc_probability = 0 instead they use a cron /etc/cron.d/php5 09,39 * * * * root [ -x /usr/lib/php5/maxlifetime ] ...
13
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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, ...
13
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5answers
137 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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3answers
43k views

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
4k 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, ...
13
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1answer
6k views

Multiple php versions simultaneously on Ubuntu

I want to be able to run multiple php versions on my development box running Ubuntu 12.04. What I want to accomplish is that when I use localhost as domain a default is used (let's say php 5.3.17). ...
12
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7answers
23k 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 ...
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3answers
2k 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
850 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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8answers
10k 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
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9answers
17k views

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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4answers
14k views

How to fix PuTTY showing garbled characters?

Connecting from a Windows 7 PC via SSH to an Ubuntu server using PuTTY, I get some screen errors: I.e. it: "Double-draws" the selection inside Midnight Commander (MC). Other characters like line ...
12
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3answers
18k 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
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4answers
8k 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: ...
12
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5answers
13k 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 ...
12
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4answers
5k 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 ] \ ...
12
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4answers
17k 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 ...
12
votes
1answer
15k 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 ...
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11answers
7k 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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7answers
19k 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% ...
12
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4answers
6k views

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

Sorry, this might be a beginner question: 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 ...
12
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1answer
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 . ...
12
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3answers
26k 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 ...
11
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19answers
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 ...
11
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3answers
52k 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 ...
11
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3answers
9k 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
votes
6answers
18k views

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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4answers
2k 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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2answers
24k 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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5answers
2k views

How to remove many (200 000) files?

I must remove 200 000 files (all of them) from a folder, and I don't want to delete the folder itself. using rm, I get an "Argument list too long" error. I've tried to do something with xargs, but ...
11
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3answers
12k views

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 ...
11
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5answers
628 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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3answers
7k views

Can't get bower working - bower ESUDO Cannot be run with sudo

I get the following error when I run bower: bower ESUDO Cannot be run with sudo Thing is, I'm not running bower with sudo. The command I run is: bower install foo or bower search cats I am ...