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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.

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 ...
25
votes
8answers
6k views

accidently ran “chown www-data:www-data / -R” as root

i just ran this a few seconds ago, i managed to do ctrl-c as soon as i realized what i started doing. so far in the only dir its started going through is /bin im afraid to do anything else, so far ...
16
votes
5answers
17k views

`sudo echo “bla” >> /etc/sysctl.conf` permission denied

Disclaimer: I'm pretty novice at sysadmin stuff. I'm trying to set up port forwarding in an AWS EC2 instance, this has to be done in the command-line because I don't want to go in and edit anything, ...
6
votes
3answers
33k views

Can't restart nginx, bind() failed (98: Address already in use)

I know this topic exists in various different forms, but I'm having trouble solving my problem. If I run service nginx restart, nginx fails with the following log: 2015/03/14 08:36:42 [emerg] 9400#0: ...
26
votes
2answers
5k views

Weird syslog order

Have you ever seen wrong order in /var/log/syslog ? I think that it causes only crontab. Jun 28 22:20:01 alex CRON[2327]: (root) CMD (something > /dev/null) Jun 28 22:21:01 alex CRON[2700]: (root) ...
104
votes
17answers
165k views

CentOS vs. Ubuntu [closed]

I had a web server that ran Ubuntu, but the hard drive failed recently and everything was erased. I decided to try CentOS on the machine instead of Ubuntu, since it's based on Red Hat. That ...
87
votes
8answers
43k views

Heartbleed: how to reliably and portably check the OpenSSL version?

I was looking at a reliable and portable way to check the OpenSSL version on GNU/Linux and other systems, so users can easily discover if they should upgrade their SSL because of the Heartbleed bug. ...
5
votes
5answers
2k views

What's needed for a complete backup system?

For my new server, I want to setup a proper backup solution. I've found a great setup that will do twice-daily incremental backups via Dropbox. I plan on backing up my various databases, the webroot ...
5
votes
1answer
3k views

How do I set permissions structure for multiple users editing multiple sites in /var/www on Ubuntu 9.10?

I'm setting up an Ubuntu server that will have 3 or 4 VirtualHosts that I want users to be able to work in (add new files, edit old files, etc.). I currently plan on storing the sites in /var/www but ...
20
votes
4answers
52k views

Linux e1000e (Intel networking driver) problems galore, where do I start?

I'm currently having a major problem with e1000e (not working at all) in Ubuntu Maverick (1.0.2-k4), after resume I'm getting a lot of stuff in dmesg: [ 9085.820197] e1000e 0000:02:00.0: PCI INT A ...
22
votes
8answers
11k views

How to configure a shortcut for an SSH connection through a SSH tunnel

My company production servers (FOO, BAR...) are located behind two gateway servers (A, B). In order to connect to server FOO, I have to open a ssh connection with server A or B with my username ...
58
votes
8answers
141k views

Apache2 config variable is not defined

I installed apache2 on ubuntu 13.10. If I try to restart it using sudo /etc/init.d/apache2 restart I get this message: AH00558: apache2: Could not reliably determine the server's fully qualified ...
30
votes
4answers
60k 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 ...
11
votes
11answers
14k views

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 ...
10
votes
2answers
7k views

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 ...
13
votes
2answers
6k views

How can I install packages without starting their associated services?

As you're probably aware, by default when you install a package on a Debian or Ubuntu based system, if the package contains a service, that service will generally be enabled and started automatically ...
10
votes
1answer
3k views

No space left on device — but there is space

I'm running an Ubuntu 12.04.1 server in a VMware virtualized environment that has a strange issue. Twice now, at seemingly random times, the machine has suddenly been unable to write to the root ...
6
votes
2answers
19k views

MySQL: Allow both remote AND local connections

In my Ubuntu's /etc/mysql/my.conf, I have: bind-address = 192.168.2.20 # My external IP It works fine from remote, but when I want to connect locally, the app that uses on MySQL says: java.net....
2
votes
1answer
10k views

Installing Ubuntu 12.04 on HP Proliant DL380e with 1TB SAS Drive

I have an HP Proliant DL380e with a 1TB SAS Drive and I am trying to install ubuntu server 12.04 on it. I have created a RAID array using Array Controller Utility and had a RAID0 logical volume ...
2
votes
1answer
2k views

Dealing with multiple private DNS servers

I'll try to explain this as best I can... I'm on ubuntu 13.04, and I am running a local BIND instance at 127.0.0.1 for access to basic wild-card DNS for development (i.e. "*.dev == 127.0.0.1" - yes, ...
76
votes
5answers
39k views

Why don't EC2 ubuntu images have swap?

I started a couple servers on EC2 and they don't have swap. Am I doing something wrong or is it that the machines just don't have any?
117
votes
1answer
71k views

How do I ask apt-get to skip any interactive post-install configuration steps?

I have a server build script which uses apt-get to install packages. It then puts pre-written configuration files directly in place, so the interactive post-install configuration dialog in packages ...
84
votes
11answers
451k views

How to start/stop iptables on Ubuntu?

How can I start/stop the iptables service on Ubuntu? I have tried service iptables stop but it is giving "unrecognized service". Why is it doing so? Is there any other method?
47
votes
3answers
100k views

How do I upgrade from PHP 5.3 to PHP 5.4.6 in Ubuntu?

Is there an easy way out to get the latest PHP? I have tried updating my package but none of it has 5.4.6 yet... if anyone knows on how to do it quickly, can it be shared here? I've tried compiling ...
27
votes
9answers
4k views

Ubuntu, how to setup a new machine like an existing one

I have one machine setup with the apps I need, and I'd like to install the same on a new Ubuntu box. Is there a script that will list all the installed apps, so that I can diff between the boxes and ...
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 ...
24
votes
3answers
59k 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
23
votes
5answers
18k views

Scripted install of MySQL on Ubuntu

I need to write a script that will build my server from a fresh Ubuntu server install. Among things like Apache and PHP it needs to install MySQL. The only problem here is that when I install MySQL ...
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 ...
23
votes
4answers
30k 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 ...
39
votes
9answers
96k 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
10
votes
8answers
22k views

Ubuntu: Resize the root LVM(2?) partition

I have an Ubuntu virtual machine running in VirtualBox 2.2.4, and I created it on an 8gb virtual disk which is too small. So, I am trying to increase the size of the disk. So far, I have done this: ...
8
votes
2answers
5k views

My cron tasks report command not found [duplicate]

This is the contents of my crontab file: 0 0,6,12,18 * * * cd /var/www/app/current && backup perform --trigger db_backup --config_file config/backup.rb --data-path db --log-path log --tmp-...
5
votes
7answers
16k views

What causes PHP pages to consistently download instead of running normally

I'm running a Ubuntu Server on a VM, to test out different web forum solutions. I have set up a ~/public_html/ to be accessible with the apache2 web server, and that works fine. However when I go to ...
5
votes
1answer
3k views

Encrypted LVM on RAID1 - Failure testing, manual mount

We have an Ubuntu 10.04 LTS server set up with LVM running on top of disk encryption, which runs on top of a RAID1 volume comprised of two physical SATA disks. The configuration looks like this: ...
3
votes
5answers
5k views

Enable access without “www.” on Ubuntu

I want to enable the access to my site without the "www." prefix. I tried to insert this in my /etc/apache2/sites-available file: <VirtualHost *:80> serverName mydomain.gov.br ...
1
vote
1answer
1k views

Postfix forwards to Gmail being rate limited even with unmodified headers

I've installed Postfix on Ubuntu 14.04 with the defaults. I then configured some virtual aliases to forward email from a few addresses to various personal (mostly Gmail) accounts. This is just to make ...
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?
67
votes
9answers
82k views

What is the debian-sys-maint MySQL user (and more)?

I have been bitten several times by the 'debian-sys-maint' user that is installed by default on the mysql-server packages installed from the Ubuntu repositories. Generally what happens is I pull a ...
17
votes
6answers
16k 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 ...
24
votes
3answers
48k 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 ...
22
votes
2answers
34k 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 ...
49
votes
7answers
56k views

protocol version mismatch — is your shell clean?

When following the instructions to do rsync backups given here: http://troy.jdmz.net/rsync/index.html I get the error "protocol version mismatch -- is your shell clean?" I read somewhere that I ...
18
votes
2answers
34k 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?
13
votes
3answers
17k views

How to redirect all outgoing email from postfix to a single address for testing

I am setting up a testing server for a web based application that sends some email notifications. Sometimes testing is performed with real customer data, and for that reason I need to guarantee that ...
22
votes
2answers
8k views

Prevent the possiblity of writing data to an unmounted mount point directory [duplicate]

I have an Ubuntu server where I'm automounting an external hard drive each boot. To do this, I've created an empty folder on the root partition, and the drive gets mounted "inside" this folder. ...
16
votes
1answer
29k 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
votes
4answers
71k views

How do I register Linux server with Windows DNS server

I have several Ubuntu machines (mostly 8.04) that I would like to register their hostnames (or desired hostnames) with my main DNS server running on Windows 2000 so that I can access these machines ...
7
votes
3answers
9k views

How do I setup sshd to require both a private key and a password?

How do I setup sshd to require both a private key and a password? In /etc/ssh/sshd_config, I currently have: RSAAuthentication yes PubkeyAuthentication yes PasswordAuthentication yes But apparently ...
5
votes
4answers
15k views

How to setup Apache NameVirtualHost on SSL?

I would like to set the A record of two DNS to point to my Ubuntu intance. Apache should then read the domain name accordingly and point the incoming request to the right physical path. I have set ...