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.
16,577
questions
65
votes
5
answers
104k
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 ...
63
votes
7
answers
114k
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 ...
63
votes
4
answers
56k
views
Purpose of Debian "sites-available" and "sites-enabled" directories?
Can anyone tell me—in a nutshell—what the purpose of these two directories are in Debian?
/etc/apache2/sites-enabled
/etc/apache2/sites-available
I notice that diffing sites-available/000-default ...
63
votes
2
answers
45k
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 - ...
62
votes
5
answers
39k
views
How can I check /dev/xvda1?
On login to EC2 (Ubuntu) instance, I see
*** /dev/xvda1 should be checked for errors ***
I can't fsck /dev/xvda1 because it is mounted, and sudo umount /dev/xvda1 fails because it is in use. lsof ...
62
votes
5
answers
85k
views
How do you use apt-get to only install critical security updates on ubuntu?
How do you use apt-get to only install critical security updates on ubuntu?
We'd like to only upgrade packages that need to be upgraded for security reasons, without upgrading all other packages.
62
votes
2
answers
153k
views
Where are the logs for ufw located on Ubuntu Server?
I have an Ubuntu server where I am blocking some IPs with ufw. I enabled logging, but I don't know where to find the logs. Where might the logs be or why might ufw not be logging?
61
votes
10
answers
101k
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 out of space on the server,= and I don't know where most of the space is used.
60
votes
7
answers
198k
views
adding password to .ssh/config [closed]
I'm using ubuntu 12.04. I'm using ssh for connecting to many servers daily, so I put their parameters in .ssh/config file; like this :
Host server1
User tux
Port 2202
HostName xxx.x.xx.x
I know we ...
60
votes
7
answers
33k
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 ...
60
votes
4
answers
204k
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 ...
60
votes
3
answers
122k
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 ...
59
votes
8
answers
121k
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 /etc/ssl/private/...
59
votes
1
answer
4k
views
Can't enter the letter 'e' over ssh [duplicate]
Right now I am experiencing some very, very weird behaviour on a Ubuntu 14.04.2 LTS server I am managing.
Connecting to the server over ssh either from cygwin(mintty) or a terminal on a Linux machine,...
59
votes
2
answers
72k
views
How do view older journalctl logs (after a rotation maybe?)
I am running docker on ubuntu 16.04 and would like to view the logs. However, I am unable to view logs after what I am guessing is some sort of rotation or the logs grow to a certain size.
I have not ...
57
votes
3
answers
128k
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 ...
57
votes
2
answers
94k
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.
But ...
55
votes
1
answer
113k
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+ ...
55
votes
7
answers
42k
views
Headless Ubuntu server machine sometimes stuck at GRUB menu
I have Ubuntu 10.10 Server installed on a single-board machine in a semi-embedded environment; no keyboard or screen, just SSH access to it.
So it's really frustrating when it occasionally boots up ...
54
votes
4
answers
238k
views
How to check cron logs in Ubuntu
I went to /var/log/cron but this file is empty.
How to check if crontab is enabled or is running properly or not in ubuntu
thanks
54
votes
7
answers
122k
views
How to get e-mail from (failed) cron-jobs in Ubuntu?
I create cron-jobs in Ubuntu by placing the executable in one of /etc/cron.{daily,hourly,monthly,weekly}. There are lots of directories starting with cron:
kent@rat:~$ ls -ld /etc/cron*
drwxr-xr-x 2 ...
53
votes
3
answers
41k
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 ...
53
votes
3
answers
123k
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 ...
53
votes
8
answers
114k
views
Ubuntu Apache: httpd.conf or apache2.conf?
which one of these two files should I use to configure Apache?
The httpd.conf is empty, while apache2.conf is not.
It confuses me!
52
votes
12
answers
66k
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 ...
52
votes
5
answers
198k
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% ...
51
votes
2
answers
20k
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.
...
50
votes
3
answers
120k
views
How do I clear the "s" permission on a directory in Linux?
I have a directory that is showing up with the permission mask drwsrwsr-x. When I try to reset the permissions to 755 the S still remains.
What is the "s" and why cant I change the permissions ...
49
votes
4
answers
52k
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 ...
49
votes
4
answers
129k
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?
48
votes
6
answers
52k
views
How do you set a locale non-interactively on Debian/Ubuntu?
Usually, I run aptitude -y install locales then dpkg-reconfigure locales to set up locale.
Now I want to put it into a shell script, how can I reliably do the following, automatically / non-...
47
votes
3
answers
101k
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 ...
47
votes
3
answers
74k
views
UFW Firewall Rules ordering?
I have the following rules on our server within UFW:
To Action From
-- ------ ----
22 ALLOW 217.22.12.111
22 ...
47
votes
6
answers
176k
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 ...
47
votes
7
answers
56k
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/...
47
votes
1
answer
108k
views
How do I tell what is running on which ports in Ubuntu?
How could I tell what is listening on which ports on Ubuntu? In other words, how do I get a list of ports that are in use?
46
votes
3
answers
359k
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 ...
46
votes
5
answers
48k
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?
46
votes
6
answers
103k
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 ...
46
votes
6
answers
125k
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 ...
45
votes
4
answers
41k
views
Ubuntu 15.10 Server; W: Possible missing firmware /lib/firmware/ast_dp501_fw.bin for module ast
I'm running Ubuntu 15.10 server on a Asrock E3C226D2I board. When I get a kernel update or run update-initramfs -u I get a warning about missing firmware:
root@fileserver:~# update-initramfs -u
...
44
votes
2
answers
28k
views
Damaged /vmlinuz and /initrd.img symbolic links after Kernel uninstall
OS: Ubuntu 8.04 LTS Server Edition
We just rolled back an kernel update using the following command:
sudo apt-get remove linux-image-2.6.24-24-server
The uninstallation was successful, but it had ...
43
votes
3
answers
101k
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 ...
43
votes
6
answers
40k
views
How do I permanently disable Linux's console screen saver, system-wide?
I've got an Ubuntu server that boots up in text mode. It rarely has a screen or keyboard attached to it, but when I do attach a screen, I usually have to attach a keyboard too, because the darn ...
43
votes
6
answers
57k
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 ...
42
votes
12
answers
37k
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?
42
votes
4
answers
83k
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 ...
42
votes
6
answers
121k
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 ...
41
votes
1
answer
102k
views
Unable to execute gcc: No such file or directory
I am running Ubuntu LTS and I'm getting errors when trying to do some of my pip install stuff, like scrapy for example. This is the error I get:
Unable to execute gcc: No such file or directory
Error:...
41
votes
2
answers
33k
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 ...