Questions tagged [centos]

Questions specific to the CentOS Linux distribution. Use this tag if your question relates to how the CentOS distribution affects your problem; do not use it if you just happen to be using CentOS and your question is about a specific configuration detail or syntax.

33
votes
2answers
61k views

BUG: soft lockup - CPU# stuck for x seconds

I've seen a few bug reports and questions (on stackexchange and elsewhere) regarding a nagging "BUG: soft lockup - CPU#<n> stuck for <dt>s!". So far, I haven't found any clue as to what ...
29
votes
1answer
65k views

Does yum's --enablerepo option only enable a repo for the current command?

Does yum's --enablerepo option only enable a repository for the duration of the current command? For example if the enabled setting in /etc/yum.repos.d/remi.repo file is set to 0 (disabled) and I ...
16
votes
2answers
74k views

How can I add an application to the Favorites section of the Applications menu in CentOS 7? [duplicate]

I have created a custom application entry in the applications menu for Eclipse as follows in a file /usr/share/applications/eclipse.desktop as follows [Desktop Entry] Version=1.0 Name=Eclipse Exec=...
8
votes
3answers
51k views

How to install g++ 4.7.2 & c++11 on CentOS 5.x?

I'm trying to install the latest stable g++ and c++11. My host did it through yum install and thought that it was the latest, but it's not, and they are now saying that this is beyond their level of ...
19
votes
4answers
44k views

How can I know which IRQ is responsible of high CPU usage

I've moved a server from one mainboard to another due a disk controller failure. Since then I've noticed that constantly a 25% of one of the cores goes always to IRQ however I haven't managed myself ...
15
votes
10answers
70k views

How to extend CentOS 5 partition on VMware?

I have a CentOS 5 virtual machine and I added 20GB more to disk size. How do I initialize and extend the available space? I tried loading GParted as well, but the drive is locked; how do I unlock it?...
20
votes
2answers
68k views

How to add an item to the Applications menu?

How can I add an application to Applications > Internet in Gnome Desktop running on CentOS 6.4? Per this old Docs link, it suggests to edit /etc/xdg/menus/applications.menu. How can I add /home/...
16
votes
2answers
37k views

What is the purpose of avahi on a RHEL 7 server?

Running a server machine with CentOS 7, I've noticed that the avahi service is running by default. I am kind of wondering what the purpose of it is. One thing it seems to do (in my environment) is ...
58
votes
1answer
65k views

Do I need to do something about “Delta RPMs disabled”?

While updating packages on our CentOS server I got the following message: Downloading packages: Delta RPMs disabled because /usr/bin/applydeltarpm not installed. Do I need to do something about that?...
37
votes
1answer
90k views

What does “systemctl daemon-reload” do?

I have a service that stopped suddenly. I tried to restart that service but failed and asked to run "systemctl daemon-reload". What it exactly do? What is a "daemon reload?"
31
votes
1answer
130k views

Where to find the Crontab logs in CentOS

First of all I'm using CentOS [root@a etc]# cat system-release CentOS release 6.5 (Final) [root@a cron.daily]# ps -ef | grep cron root 982 1 0 Jun14 ? 00:01:15 crond root ...
16
votes
4answers
21k views

Package bash-completion missing from Yum in CentOS

I am trying to get tab-completion working in Yum in CentOS 6 (so I can do something like yum install firefo<TAB> and get back firefox), and I have found many tutorials which say to simply do yum ...
9
votes
1answer
8k views

Xvfb or Firefox throwing errors & gratuitously logging

per the answer to this question, I'm running Xvfb to make a virtual display so firefox will run on my CentOS server. (I don't need to see firefox or do any actual key or screen input/output with ...
2
votes
2answers
41k views

(CentOS) default FTP (SFTP) Log File?

I'm on CentOS v6.4 and using its native FTP Server, which i suppose is sftp. (Am i right?) Now i can use FTP well. But i need to log the actions taken by Users. Logs for the actions, such us, who ...
19
votes
3answers
132k views

How do I install the stock CentOS repositories?

I have a situation where the stock repo files that should exist in /etc/yum.repos.d/ (like centos-base.repo) are not present. I need to get them installed. I am sure this is simple, but after hours of ...
18
votes
3answers
87k views

“Last” command: How to show latest user login?

As I know, the last command shows recent logins by all users. But my PC (CentOS) has been used for roughly a year, and there are many users logged. I tried to used the last command, but it just showed ...
17
votes
5answers
53k views

ldd tells me my app is “not a dynamic executable”

I have a 32-bit application (called uclsyn) I received from an astronomy professor. I managed to get it running on CentOS a year ago, but now when I am setting up a new CentOS VM, it won't run and I ...
12
votes
3answers
33k views

How to install packages to a custom location in centos6

This is a set up I am doing for a college to promote Linux use in their labs. I have a shared location, let me call it /tp; I want to install all my libraries and packages in this location just like ...
11
votes
0answers
6k views

OpenSSL Package Rebuild CentOS 6.4 [closed]

Rebuilding openssl with Elliptic Curves on CentOS 6.4 The strategy is: 1) Download the "official" CentOS source package (.src.rpm) 2) Modify the .spec file to enable elliptic curves. (change no-EC ...
8
votes
3answers
58k views

How to manually configure a monitor in CentOS7, attached via KVM?

I have a fresh desktop install of CentOS7 with Gnome 3. I need to use this machine with a KVM but for some reason CentOS7 cannot detect my monitor through the KVM I have, so it defaults to "Unknown ...
6
votes
1answer
3k views

Unable to swapoff but enough physical memory is available

I have a weird problem with turning off the swap. The server has 192 GB of memory, 154 GB free. It's a Hypervisor running a number of Linux KVM Virtual Machines. When trying to: # swapoff -a ...
5
votes
2answers
8k views

yum - list configure flags/options used to compile package

How can I see a list of flags/options used to configure and compile a certain package in yum, without having to install it first? Say apache, for example. $ yum list available httpd Available ...
4
votes
2answers
23k views

Set Static IP in CentOS 6.4?

Most guides seem to revolve around modifying ifcfg-eth0, which doesn't exist on my system.. [root@Azaz07]# vi /etc/sysconfig/network-scripts/ifcfg-eth0 [root@Azaz07]# ls /etc/sysconfig/network-...
3
votes
2answers
6k views

VirtualBox Kernel Module Installing Issue

I installed VirtualBox, in the first run i got this warning: WARNING: The vboxdrv kernel module is not loaded. Either there is no module available for the current kernel (3.10.0-...
25
votes
7answers
141k views

Increasing Screen Size/Resolution on a VirtualBox Instance of Centos

I have VirtualBox instance of Centos 5. The screen size is quite small (800*600) and I'd like to increase it to 1280*1080. Under the Gnome preferences for "Screen Resolution" I only get the option for ...
15
votes
4answers
22k views

How to install man pages on centos?

Note: This applies to Centos 7. If you are looking for a Debian answer, see this question. Those answers will not be duplicated here. After an install of centos 7, I can't access man pages : # man ...
11
votes
1answer
4k views

Where are the CentOS 6.4 documents?

I'm only able to find up to version 5 on CentOS.com: http://www.centos.org/docs/ Even though CentOS 6 was released back in mid-2011..
5
votes
1answer
28k views

How do I list all available SSL CA certificates on CentOS 6?

It's difficult to tell whether I've succeeded in trusting a given certificate, after I have installed it, especially for root CAs. To check whether I have successfully installed a certificate without ...
5
votes
2answers
17k views

No network connection in CentOS 6.3 Minimal under VMWare Player

I'm trying to replicate in VMWare Player the exact same conditions I have under my Dedicated Server for testing purposes. Now, the thing is that that when I try to install something, or ping http://...
5
votes
3answers
18k views

What commands are available in the %pre section of a Kickstart file on CentOS?

Environment: CentOS 5.5 and 6.4 I have a request to analyze the hardware before installation to make sure our customers don't install our software on sub-standard server hardware. For example, ...
4
votes
1answer
9k views

CentOS doesn't know what the internet is

So I've done my share of investigating this problem... I just recently created a CentOS 6 VM on my LinuxMint box using VirtualBox. I left all the recommended values the same upon creation (8GB HDD, ...
16
votes
1answer
1k views

Why does oot say “hey” in usleep -o?

On a Centos 6.6 box I noticed this... [root@abcd /]# usleep --help Usage: usleep [microseconds] -v, --version Display the version of this program, and exit -o, --oot oot says hey! ...
10
votes
5answers
46k views

a tpm error (7) occurred attempting to read a pcr value in centos

I'm getting this error while booting and my computer won't start. a tpm error (7) occurred attempting to read a pcr value I installed CentOS 7 on a z400 workstation computer. I was working on it ...
8
votes
2answers
12k views

No manual entry for man

I'm working in a Centos 6.6 Docker image. I thought I installed everything to get access to man pages, but apparently not... $ yum install -y man man-pages man-pages-overrides [...] Complete! $ ...
7
votes
3answers
4k views

Enabling system management privileges for non-local users - How the heck does `polkit` work, anyways?

I am managing a CentOS 6.2 server remotely using X over SSH (actually NX, but that's just a proxy). The Everything is working correctly, except when I try to do tasks that would normally require ...
7
votes
4answers
47k views

What prevents a machine from responding to pings?

I have a CentOS release 5.4 linux box on Amazon EC2 that I'm trying to set up to be monitored via Nagios. The machine is in the same security group as the nagios server, but it seems to be ...
5
votes
7answers
676 views

Are there additional ways to protect SSH connections besides firewall and RSA Keys?

Sometimes I don't have a static IP and need to administrate my web server remotely. I'm looking for any additional layers of protection I could add to make opening port 22 safer. Currently I have ...
5
votes
2answers
26k views

Problems with CMake in CentOS 6

I try to install a software in CentOS 6.2, without success. In README file it says: Requirements: - qt4 gui lib version >= qt4.6.x Note that many linux distributions split packages into a ...
5
votes
1answer
1k views

GNOME 3: bottom panel window order

I have centos 7.1. At bottom panel opened windows (running applications) are represented (ex: openoffice, thunrderbird, terminal). Question one - How can I change the order of these opened windows (ex:...
2
votes
2answers
2k views

why nginx holds file descriptions of logs?

on Red Hat Enterprise Linux Server release 6.6 (Santiago) nginx version: nginx/1.0.15 I use common nginx logrotate config, logrotate works fine and nginx creates new log file like access.log or error....
2
votes
1answer
744 views

SELinux + MergerFS (fuse) not working well together

I have been trying now for several days to get my new server up and running. I am running CentOS with MergerFS to pool my drives and samba to host to my windows machines. All of this running in ...
0
votes
1answer
17k views

How can I extend VMware Partition on Centos 7 using GParted?

I've a problem with increasing a partition from 20GB to 120GB, VMDK file. Here is what I've done: using vmware-diskmanager to increase vmdk file from 20 GB - 120 GB. It's ok. download and boot from ...
14
votes
2answers
5k views

Should you run automatic updates

I'm running production Centos web servers. I want to know what is best practice for running updates. Should I automate this with yum-cron or yum-updatesd? Or is there a danger of updates breaking ...
14
votes
2answers
45k views

apache won't restart after adding VirtualHost conf file, why not?

In a CentOS 7 server, I get the following error when I type sudo apachectl restart after I add an include file at the bottom of httpd.conf: Job for httpd.service failed. See 'systemctl status httpd....
9
votes
6answers
23k views

Chrooted SFTP user write permissions

I have a setup with sftp only users: Match Group sftponly ChrootDirectory %h ForceCommand internal-sftp AllowTcpForwarding no I get the following message in my secure.log: fatal: bad ...
9
votes
3answers
8k views

mv: cannot move “home” to “home-old”: Device or resource busy

I want to replace /home with a symlink to my nfs-mounted home dirs. Only root is logged in, /home is not a separate filesystem, lsof shows no locks, selinux is permissive. What am I missing? I'm ...
8
votes
4answers
6k views

Dirty COW exploit CVE-2016-5195

This morning we discover this exploit CVE-2016-5195 How do we patch CentOS kernel? is there any patch available? http://www.cyberciti.biz/faq/dirtycow-linux-cve-2016-5195-kernel-local-privilege-...
7
votes
3answers
21k views

CentOS use .pac file as proxy

I have to use a proxy with authentication to connect to the Internet. But I can't find any solution for this. I have modify my yum.conf, with a lot of possibilities: proxy=http://myproxy.domaine.com:...
7
votes
1answer
968 views

Pulling all of a process's swapped memory out of swap

How would one go about quickly pulling all of a process's swapped memory out of swap without writing to disk? The context on this issue is trivial, as the systemic issue necessitating the question ...
7
votes
2answers
10k views

Is it possible to add an item to the Nautilus right click menu in CentOS?

I want to add an item to my right click menu, and run a command when a user clicks on it. I'm using Centos 6.2, is it possible? If yes please tell me how I can do this.