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Questions tagged [ubuntu]

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.

41
votes
4answers
46k 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 ...
41
votes
3answers
294k views

How to check my PHP and MySQL version on Ubuntu VPS?

HI I am going to install MyBB but I am not sure whether I have installed the correct version of PHP and MySQL. PHP version 5.1.0 or above with XML Extension installed MySQL version 4.0 or ...
41
votes
6answers
47k views

How to disconnect from lxc-console

I'm working with lxc in Ubuntu 12.04, and it's really great. However, I am unable to disconnect from a lxc-console session after I've connected. I read somewhere that Ctrl-aq will disconnect me from ...
41
votes
5answers
18k views

Given a debian source package - How do I install the build-deps?

I have a debian (well technically ubuntu) source package, i.e. the .dsc, the .tar.gz, etc., I want to build this. The dpkg-buildpackage fails, since I don't have all the build dependencies. Normally ...
40
votes
6answers
49k 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 ...
40
votes
4answers
78k 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 ...
39
votes
9answers
99k 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
39
votes
3answers
80k 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 ...
38
votes
4answers
25k views

ssh: “Agent admitted failure to sign using the key”

I'm trying to set up password-less login with ssh on Ubuntu Server, but I keep getting: Agent admitted failure to sign using the key and prompt for password. I have generated new rsa keys. Before ...
38
votes
5answers
4k views

How do I empty /dev/null? [closed]

I am using Ubuntu 10.10. I am generally good with computers but mostly with Windows, I'm not very familiar with Ubuntu. I'm trying to setup a website and I'm talking with a friend I have who works ...
38
votes
6answers
108k views

Unknown/unsupported storage engine: InnoDB | MySQL Ubuntu

I recently upgraded from the previous LTS Ubuntu to Precise and now mysql refuses to start. It complains of the following when I attempt to start it: ╰$ sudo service mysql restart stop: Unknown ...
38
votes
10answers
46k views

Unzipping files that are flying in through a pipe

Can I make unzip or any similar programs work on the standard output? The situation is I'm downloading a zip file, which is supposed to be unzipped on the fly. Related issue: How do I pipe a ...
37
votes
3answers
129k views

Install openssl-dev on Ubuntu server

In order to compile NGinx in need to install openssl and openssl-dev (I'am following a book guide). So i'am doing this : sudo apt-get install openssl openssl-dev But i get an error telling me that ...
37
votes
6answers
103k views

Improving TCP performance over a gigabit network with lots of connections and high traffic of small packets

I’m trying to improve my TCP throughput over a “gigabit network with lots of connections and high traffic of small packets”. My server OS is Ubuntu 11.10 Server 64bit. There are about 50.000 (and ...
36
votes
10answers
15k 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
138k views

Where to set java heap options (e.g. -Xmx) for Tomcat 6 under Ubuntu 9.04?

I'm running Tomcat using the tomcat6 package from Ubuntu 9.04, which makes a daemon out of Tomcat using jsvc. I'd like to know the proper way to set Java heap options like -Xmx for Tomcat. I'd like to ...
36
votes
7answers
74k views

What is the preferred method to restart networking in Ubuntu and Debian

When I restart the network using: /etc/init.d/networking restart I get this warning: Running /etc/init.d/networking restart is deprecated because it may not enable again some interfaces So what's ...
35
votes
3answers
12k views

How do you Install PHP5 without installing Apache in ubuntu?

Is it possible to install PHP5 without installing apache, in Ubuntu? If so, how?
35
votes
4answers
99k 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 ...
35
votes
2answers
15k 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 ...
35
votes
8answers
37k views

Why rsync is faster than NFS?

Few days ago I noticed something rather odd (at least for me). I ran rsync copying the same data and deleting it afterwards to NFS mount, called /nfs_mount/TEST. This /nfs_mount/TEST is hosted/...
35
votes
2answers
62k 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 ...
34
votes
7answers
31k views

Logging a Daemon's Output with Upstart

I have a custom daemon that is managed by upstart on my Ubuntu server. It works perfectly except that I need to capture (log) the daemon's output. The official stanzas page says that I can use console ...
33
votes
9answers
60k 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
33
votes
7answers
116k 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, ...
33
votes
3answers
71k views

Linux: how to give a user permission to restart apache?

I have a script running under a non-root user which, under certain conditions, should restart apache httpd. What would be the simplest way for me to allow the user to do that? I'm using Ubuntu ...
32
votes
3answers
26k views

Change default directory when I SSH to server

I was wondering if there is a way to change the default directory that I get put into after I SSH into my Ubuntu server. 99% of the time when I'm logging into my server, it is to access files within ...
31
votes
6answers
27k 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) ...
31
votes
7answers
113k views

add new user with root access in Linux

I want to add new user and have/grant that new user to have all the root access, how can I do that ? I did sudo adduser --system testuser but this is not working as I expected. Thanks for help.
31
votes
14answers
20k views

File Server - Storage configuration: RAID vs LVM vs ZFS something else…?

We are a small company that does video editing, among other things, and need a place to keep backup copies of large media files and make it easy to share them. I've got a box set up with Ubuntu ...
31
votes
2answers
51k views

Straight forward way to run ssh-agent and ssh-add on login via SSH?

I'm trying to have the following commands be auto-executed when I login to my server via ssh: ssh-agent /bin/bash ssh-add ~/.ssh/id_rsa My ssh key has a passphrase and I'm fine with entering it once ...
30
votes
4answers
61k views

Forwarding ports to guests in libvirt / KVM

How can I forward ports on a server running libvirt/KVM to specified ports on VM's, when using NAT? For example, the host has a public IP of 1.2.3.4. I want to forward port 80 to 10.0.0.1 and port 22 ...
30
votes
11answers
19k views

Find last time update was performed with apt-get

I need to find the last time that the apt-get update command was run on my server. How can I determine this information?
30
votes
1answer
61k views

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+ ...
30
votes
3answers
28k 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 ...
30
votes
5answers
84k views

Why should I enable IO APIC in VirtualBox?

What are the advantages of checking the "Enable IO APIC" option in VirtualBox? While I can't find any information on advantages when I google it, two disadvantages are clear. First, it can break ...
29
votes
3answers
19k views

SSH connection lost during server upgrade - How to reconnect to process?

So, I was performing an Ubuntu Server upgrade from 11.04 to 11.10. I forgot about it in the background, and my SSH client timed out and disconnected (putty on Windows, go figure). The last thing on ...
29
votes
3answers
85k 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 ...
28
votes
9answers
34k views

Calculate MD5 checksum of a directory

I'm looking for a quick way to compare directory contents. Is it possible to do an md5sum (or equivalent checksum) of an entire directory? Using Ubuntu Linux
28
votes
10answers
78k views

How do I find out whether a port is available on Ubuntu 8.04?

Is there any command I can run from bash that will tell me whether a port is already open?
28
votes
10answers
13k views

Are configuration management tools (Puppet, Chef) capable of keeping installed packages up to date?

This is probably a simple question for those of you already running configuration management tools. Are configuration management tools such as Puppet or Chef the right approach for keeping installed ...
28
votes
6answers
4k views

How do I find out where the web site's code resides?

The facts: there is a website this website is accessible via www.example.org there is an EC2 instance which very likely keeps the website the server is Apache the server OS is Ubuntu I have full ...
28
votes
4answers
33k views

Testing whether jumbo frames are actually working

Is there a command to test whether jumbo frames are actually working? i.e. some sort of "ping" that reports whether or not the packet was broken up along the way. I've an ESXi host with an Ubuntu VM ...
28
votes
8answers
19k 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 ...
28
votes
3answers
53k 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 ...
28
votes
3answers
70k views

nginx without server_name and using only static ip address?

this is my first web app deployment and am running into all sorts of issues. I am currently going for a nginx + gunicorn implementation for the Django app, but mostly this question relates to nginx ...
27
votes
6answers
40k 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?
27
votes
7answers
38k views

Why can't I access my CouchDB instance externally on Ubuntu 9.04 server?

Update: I got it working now. Jim Zajkowski's answer helped me detect that my /etc/init.d/couchdb reboot calls weren't actually rebooting the instance. After I manually killed the CouchDB processes ...
27
votes
5answers
38k views

associate name with ip for ssh?

Let's say I just have an ip address for a server and I don't have a domain with it (it's just a database server, so it doesn't need a domain). I don't want to have to remember the ip address every ...
27
votes
2answers
18k views

debian packages version convention

I'm using debian/Ubuntu, and get confused about versions of packages. When using dpkg -l command, I get: ii vim 2:7.3.429-2ubuntu2.1 Vi IMproved - ...