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6
votes
2answers
16k views

iptables: forward port 80 to port 8080

How can I port-forward port 80 internally to port 8080? My goal is to have a web app server (Glassfish) running on port 8080, but for the outside world to access it normally on port 80. This is ...
3
votes
3answers
3k views

SELinux preventing Apache from writing to a file

SELinux is preventing the apache user from writing to a log file which it owns. When I do setenforce 0 it works. Otherwise it shows this error IOError: [Errno 13] Permission denied: ...
7
votes
2answers
1k views

yum-security for CentOS?

Last time I checked I was able to install yum-security in CentOS but since it doesn't use the official redhat mirrors I was unable to get it to actually work. Is there a way to make yum-security work ...
4
votes
2answers
374 views

Which Red Hat / CentOS updates should be applied and on what schedule?

I'm subscribed to the CentOS-announce mailing list and I've read the definitions of the various severity tags such as Critical, Important, Moderate, Low, BugFix, etc. but I'm still unclear as to what ...
3
votes
5answers
762 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 ...
2
votes
2answers
26k views

Postfix: lost connection with *somehost* while receiving the initial server greeting

I had Postfix installed on CentOS earlier (several months ago) and it was working fine. Due to the fact of the many brute-force attempts and considering that I didn't use it almost at all I shut ...
2
votes
2answers
5k views

Postfix: send all bounce messages to postmaster

The situation is that we have a number of guests, say 80, sending through a central mail infrastructure out to the web. The way the network is setup the mail server cannot necessarily initiate ...
1
vote
2answers
6k views

Centos: multiple IP addresses

I just bought 10 extra IPs from my host. How do I point these at my CentOS 5 server?
0
votes
5answers
866 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 ...
1
vote
2answers
7k views

CentOS PHP cURL NSS error 5938

Having a strange issue with cURL and PHP on a couple of CentOS boxes. Locally, I'm running CentOS 6.3. Remote is CentOS 5.9 Locally, the box receives a request, scp's a file to the remote server, ...
1
vote
1answer
2k views

How do you run Nginx on port 8080 and Apache on port 80 on the same box?

I want to install Node.js on my box (CentOS 5) for testing and sandboxing but I can't uninstall Apache as recommend by developers using Nginx. So what I'd like to do is have Nginx serving ...
0
votes
2answers
454 views

High apache load but zero traffic

I have a problem with new server.. I use VPS Centos with 1GB of ram and I use wordpress CMS. The traffic <100 visitor/hour, but the apache have high load and make the server hang with zero free ...
0
votes
2answers
675 views

Centos - Automatically issue a command after rebooting

I need to automatically issue a command on my CentOS 4.8 server after it reboots and/or powers up. Can someone please tell me where I can place this? Is there a configuration file somewhere for this? ...
67
votes
5answers
59k 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 ...
34
votes
4answers
70k views

how do you create an ssh key for another user?

I'm trying to create an ssh key for another user. I'm logged in as root. Can I just edit the files generated by ssh-keygen and change root to the user I want?
16
votes
7answers
21k views

Automatically check for Security Updates on CentOS or Scientific Linux?

We have machines running RedHat-based distros such as CentOS or Scientific Linux. We want the systems to automatically notify us if there are any known vulnerabilities to the installed packages. ...
12
votes
1answer
2k views

Apache, suexec, PHP, suPHP

While I'm quite comfortable as a Linux user, my Linux Admin-fu is a bit weak. Thus, I'm here looking for guidance with a CentOS server I'm about to build. I need to setup an Apache2 web server for a ...
8
votes
4answers
21k views

how do I disable the nf_conntrack kernel module in CentOS 5.3 without recompiling the kernel

I'm running CentOS 5.3 and want to disable the nf_conntrack module to improve network performance for haproxy. I'm running iptables with some simple rules. I don't really need the connection ...
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
13k 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 ...
10
votes
5answers
13k 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 ...
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 ...
3
votes
3answers
7k 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 ...
2
votes
2answers
9k 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 ...
30
votes
5answers
56k 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 ...
15
votes
2answers
21k 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 ...
13
votes
3answers
8k 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 ...
2
votes
2answers
6k views

Setting up two NICs on two separate LANs provides error

I wish I had found this before starting in, but it's too late for that... I am running CentOS 5.5. I started following this guide for setting up two NICs on different networks. Everything was ...
19
votes
3answers
5k views

Should I be worried that yum update suddenly wants to update well over 100 packages on my CentOS 6 system?

I get an email alert whenever there's something to update, and typically do them that day. This tends to happen most days. For whatever reason I've had no alerts since 20th July until today (I ...
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 ...
8
votes
3answers
543 views

Best choice for NTP client configuration

Lets see if someone can throw a bit of light on this subject.. I'm making a server installation in the next days. My client wants to deploy a Hortonworks HDP with 2 servers as master servers and 5 ...
7
votes
4answers
8k 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 ...
4
votes
1answer
4k 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. ...
3
votes
2answers
426 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 ...
2
votes
3answers
267 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 ...
8
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 ...
4
votes
3answers
8k views

ldap force user to change password

I am using CentOS-ds (based off Redhat-DS and 389 directory servers). I have LDAP setup, and working to authenticate users (and Sudo, thats a handy feature!). even passwd is working great to change ...
3
votes
4answers
5k views

CentOS - PHP - Yum Install with Custom ./configure params

I have successfully configured and compiled php on my dev server, and works great, but after talking to a sysadmin buddy, he informed that custom compiles of the latest builds are not recommended for ...
2
votes
2answers
4k views

Kernel update without reboot [duplicate]

Possible Duplicate: Reloading a kernel “live” in CentOS / RHEL 6 How can i update kernel on Centos without reboot .? I found ksplice but it is not supported for Centos. ...
1
vote
4answers
3k 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
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
4k 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.
14
votes
3answers
12k 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 ...
8
votes
6answers
13k views

httpd dead but subsys locked

I modified today max_execution_time in php.ini, when I restarted the server, I get this error : Stopping httpd: [FAILED] Starting httpd: (98)Address already ...
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 ...