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70
votes
11answers
12k views

How bad is it really to install Linux on one big partition?

We will be running CentOS 7 on our new server. We have 6 x 300GB drives in raid6 internal to the server. (Storage is largely external in the form of a 40TB raid box.) The internal volume comes to ...
47
votes
5answers
43k views

“POSSIBLE BREAK-IN ATTEMPT!” in /var/log/secure — what does this mean?

I've got a CentOS 5.x box running on a VPS platform. My VPS host misinterpreted a support inquiry I had about connectivity and effectively flushed some iptables rules. This resulted in ssh listening ...
17
votes
1answer
49k views

What does “<service_name> dead but subsys locked” mean?

I'm trying to run memcached on a centos box and it runs for a while, but then ends up in this state: memcached dead but subsys locked netstat shows this: tcp 0 0 :::11211 ...
6
votes
9answers
4k views

Linux Server Performance Monitoring

I'm looking to monitor performance on my Linux servers (which happen to be Centos). What are the best tools for monitoring things in realtime such as: Disk Performance I/O, swapping etc.. CPU ...
5
votes
2answers
3k views

Tips for optimizing RHEL/CentOS kickstart workflow

I'm working in an environment that consists of CentOS systems located in multiple data centers and office locations. I've been using a reasonable kickstart with a solid post-install script, but want ...
4
votes
2answers
10k views

Stop DoS attacks with an IP tables rule?

I was wondering if I could prevent small (D)DoS attacks with a simple IP tables rule? By small I mean that they are flooding my web server with about 400+ requests from one or two IP addresses. I ...
3
votes
3answers
6k views

cakephp & nginx config/rewrite rules

Hi somebody please help me out, I've asked this at stackoverflow as well but not got much of a response and was debating whether it was programming or server related. I’m trying to setup a cakephp ...
11
votes
2answers
19k views

How do I get SELinux to allow Apache and Samba on the same folder?

In the configuration I have setup I wish to allow samba and apache to access /var/www I am able to set a context to allow samba access, but then httpd doesn't have access. Using setenforce to 0 ...
7
votes
4answers
11k views

Install recent ImageMagick on CentOS 6.3

I'm having a terrible time trying to get a recent version of ImageMagick installed on a CentOS 6.3 x86_64 server. First, I downloaded the RPM from the ImageMagick site and tried to install it. That ...
7
votes
1answer
7k views

How do I view the contents of a SELinux policy package

As the title says, how do I view the contents of a SELinux policy package? The resulting files end with .pp. I'm running on centos 6, but I guess it's the same way on "all" distros. For example ...
2
votes
2answers
7k views

Mount a Windows DFS Namespace in Linux

I've got a Windows DFS setup with a few namespaces, and I need a way of accessing them via CentOS. Any ideas? I've had a look at CIFS mounting, but it won't support the namespace (each separate ...
22
votes
5answers
42k views

How do I change timezone in centos 6.2?

Here is the output of my date command: [root@r1304 ~]# date Wed Apr 18 15:43:28 GST 2012 I want to change the default system timezone to Asia/Dubai. I've followed a tutorial and did this: ln -sf ...
13
votes
2answers
6k views

Linux containers (LXC) on Red Hat/CentOS EL6 - lxc-create versus libvirt?

It's tricky trying to stay within the good graces of Red Hat and still plan for system longevity... I've been a proponent of Linux Containers (LXC) for over a year. My initial installations were ...
14
votes
4answers
6k views

Improving IO with FlashCache

I have a server with 2 HDD's (2x 1 TB), running in RAID 1 (SW-RAID). I want to improve IO performance by using flashcache. There are running KVM virtual machines on it, using LVM. Regarding this, I ...
7
votes
4answers
7k views

File audit in Linux: how to watch directory tree for deletions?

I have a forum script running on server and somehow small number of attachments begin to get lost. I want to find out what is deleting them and at what time. How can I setup Linux auditd (auditctl) to ...
3
votes
1answer
3k views

SELinux: Letting Apache talk to MySQL on CentOS

So I have chrooted MySQL into /opt/chroot/mysql, and everything runs fine. Apache is configured normally, and also runs fine. I created a small PHP script which connects to the MySQL Daemon, and ...
3
votes
1answer
1k views

Cent OS upgrade PHP

I'm in the midst of resolving a bunch of security issues on a clients server to get them compliant with credit card laws and such. The first order of business is getting php from 5.2.14 to 5.2.16. ...
2
votes
3answers
259 views

Any good resources for setting up a webserver in Linux?

Are there any good resources (videos, ebooks, websites, etc) which allow you to self learn how to configure and manage: Securing a server Web Server (Apache, PHP, MySQL, Perl, TomCat, etc) Mail ...
16
votes
4answers
22k views

How do I patch RHEL 4 for the bash vulnerabilities in CVE-2014-6271 and CVE-2014-7169?

A mechanism for remote code execution through Bash has been widely reported yesterday and today (September 24, 2014.) http://seclists.org/oss-sec/2014/q3/650 Reported as CVE-2014-7169 or CVE-2014-6271 ...
10
votes
2answers
5k views

HowTo redirect HTTP to HTTPS on the same httpd?

Here is what I have got: CentOS 5.4 (32-bit) installed Apache httpd (Server version: Apache/2.2.11 (Unix)) mod_rewrite already presents Question: how to redirect simple http://site.com to ...
7
votes
2answers
2k views

What can cause ALL services on a server to go down, yet still responding to ping? and how to figure out

It has happened to me already twice within very few days that my server goes down completely, meaning http, ssh, ftp, dns, smtp, basically ALL services stop responding, as if the server had been ...
7
votes
2answers
14k views

CentOS /usr/local/lib system wide $LD_LIBRARY_PATH?

I install custom software in /usr/local/lib. How do I set the PATH and LD_LIBRARY_PATH in CentOS 6 system-wide to use /usr/local/lib. I realize there may be more than one way. What's the simplest and ...
3
votes
2answers
407 views

MediaWiki is getting slower gradually

I set up my MediaWiki on a CentOS. In the first few months, it works fine and fast. But it seems gradually getting slower. My wiki site has less than 50 pages, so it's a very small scale site. But it ...
1
vote
3answers
3k views

Centos Xen resizing DomU partition and volume group

I have a setup like so: Dom0 LV | DomU Physical Disk | | XVDA1 XVDA2 (/boot) (DomU PV) | VolGroup00 (DomU VG) ...
0
votes
2answers
3k views

SMTP server for centOS, other than Postfix? [closed]

I need to install smtp server on centOS, but I don't want to use postfix. please suggest some others smtp servers and how install using putty.
13
votes
3answers
9k views

Installing Fedora RPMs in CentOS

How safe is it to install Fedora RPMs in CentOS 5? Does it depend on the version of the Fedora RPM or is it generally better to steer clear?
12
votes
1answer
2k views

Linux - if I change the hostname, which services need to be restarted?

I'm making some system hostname changes across a few environments and this got me thinking... When I change a server's hostname (live), what needs to be modified and which system services require a ...
5
votes
3answers
2k views

iptables — OK, **now** am I doing it right?

This is a follow up to a previous question where I asked whether my iptables config is correct. CentOS 5.3 system. Intended result: block everything except ping, ssh, Apache, and SSL. Based on ...
5
votes
1answer
2k views

How do I migrate from RHEL 5 to CentOS 5?

I've found myself in charge of installing some software on an old server running RHEL 5. Unfortunately, since it's just a development server now, it no longer rates a license. I'd like to continue ...
4
votes
2answers
1k views

How to setup PXE boot server in CentOS

I am working on researching a project for work and thought that I would ask for your advice. I am trying to find out how to setup a PXE boot server within CentOS that would allow us to PXE boot a ...
3
votes
1answer
13k views

CentOS 7 x64 and HP Proliant DL360 G5 SCSI Controller compatibility

I've an HP Proliant DL360 G5 server with two 72gb HDD in RAID and 2 150gb HDD in RAID. I've Windows Server installed on the 72gB HDD and I'm now trying to overwrite it with a fresh installation of ...
3
votes
5answers
437 views

Is there a way to run kickstart scripts on a pre-existing server?

We normally provision servers using kickstart scripts (served by Cobbler) when installing the operating system. But we are to be given a new server from an ISP that already has the operating system ...
3
votes
3answers
2k views

Changing Timezone, Centos Apache server

I'm trying to change my server's timezone. I was following this tutorial but I can't get it to change to Pacific Standard Time. ln -sf /usr/share/zoneinfo/EST localtime Will work, but ln -sf ...
2
votes
2answers
388 views

MySQL not using specified RAM anymore

A few days ago I got a new machine setup running CentOS 5.6 (64bit), with 12GB ddr3 ram, 4x SAS 15k rpm drives in RAID10. On this machine I'm running MySQL Server version: ...
2
votes
3answers
3k views

CentOS 5.5 remote kickstart installation stalls at “Starting install process.” How to debug?

I'm having a difficult time with a remote CentOS 5.5 kickstart installation on an HP ProLiant DL360 G6. This is in an environment where I maintain an internal CentOS yum repository. The kickstart ...
2
votes
4answers
6k views

Recommended method to upgrade PHP 5.1.6 to 5.2.x on CentOS 5.4

It's been awhile since this type of question was asked here. Perhaps the recommended solution has changed. I have a CentOS 5.4 mail server running RoundCube webmail. By default, RoundCube expects PHP ...
1
vote
2answers
413 views

CentOS 6 - Kernel 3 from CentOS 7 Repo?

i want to run kernel 3 on centos 6. I found out, that it cant get installed over yum and i would need to compile it by my own. My question: Could i use the centos 7 repo to install kernel 3.x from ...
1
vote
1answer
407 views

Apache Dynamic Virtual Host with SSL [duplicate]

I have the following in my httpd.conf file NameVirtualHost *:80 <IfModule mod_vhost_alias.c> <VirtualHost *:80> ServerAlias * UseCanonicalName Off LogFormat "%V %h %l %u %t ...
1
vote
1answer
653 views

Centos 5 Full backup

so I have my dedicated server that is set to expire tomorrow. What I need to do is a full backup of everything, with the OS and everything on it. And when I say full backup, I mean a backup that can ...
1
vote
4answers
868 views

CentOS Hot Backup

We have dedicated CentOS machine running a customer management service, in a few days development will cease and we would like to take a complete backup of the hard-disks. The server has 2 500GB ...
1
vote
4answers
2k views

Apache uses up a lot of CPU for small website

I have a CentOS 5.5 VPS server with 512MB RAM setup. There is 1 website hosted on it through Apache/PHP/MySQL which is built in Magento, a popular ecommerce framework. When I browse the website, it ...
1
vote
2answers
1k views

Migration from Xen to KVM

I have Xen domU virtual machines running Windows. Each of them are installed in their own LVM logical volumes. I want to migrate them to another server with KVM on lvm to. How can I do this faster ...
1
vote
2answers
6k views

how to install git on CENTOS 5.5

How can I install git on CENTOS 5.5 machine? I tried to install it from yum but got following msg. root@host [~]# sudo yum install git Loaded plugins: fastestmirror Loading mirror speeds from cached ...
1
vote
5answers
5k views

Postfix Stagger/Rate Limit Outbound Mail

We have a server that sends our weekly newsletter to subscribers, To prevent people like Hotmail or Yahoo from blocking us due to sending too many simultaneous emails to them, Is there a way we can ...
1
vote
4answers
528 views

Should Swap be used like this?

I have a server with Dual Nehalem Quad Core Xeon 5520 and 12GB DDR3 RAM. The server's average memory usage is only around 10-15%, yet the Swap used shows 10%+. Is this normal, or could something be ...
0
votes
1answer
352 views

installing SSL certs on apache … what certs to use?

Im an intermediate Linux user and got assigned the task to make Apache run https connections. Currently running centOS 6 and my problem is following: installed mod_ssl and tried to set up paths ...
0
votes
1answer
2k views

Puppet yum repo - Pull down 2.7.x vs 3.0.x

So a few weeks ago I started on the path to using puppet to automate all the configs/services. At the time I was using the EPEL repo, which installed version 2.6.x. After some reading I was trying to ...
0
votes
5answers
828 views

Limiting bandwith per user?

We need to modify our bandwidth usage (per user on our site). I would want to limit bandwidth per ip,,. Basically we want the users who connects to our webstie to only be able to (download @ 2.5Mbps ...
0
votes
1answer
2k views

Configrue Exim Sendmail for relay

I have a VPS server at UltraHosting.com and requires that I use "Smart Relay" when sendning emails. However I cannot send mail using the php mail() function. Here is an article they have on Smart ...
0
votes
1answer
246 views

Linux (CentOS) - Is there any (feasible) way to add a file write “hook”?

I have a mod_security log parsing script to load data into a mysql database which is then accessed by our Project Management System to display recent flaggings by the rulesets for our developers. The ...