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Intermediate Linux / Unix System Administrator Tutorials

These tutorials assumes that you have strong understanding of Unix like operating systems and very comfortable with most aspects of the Unix/Linux operating system. Familiar with fundamental networking/distributed computing environments is required. ( rss feed )

How To PFSense Configure Network Interface As A Bridge / Network Switch

I have Soekris single board communication embedded computers which is optimized for low power and network usage. The server has four Ethernet ports. I’ve installed PFSense firewall on it and configure WAN + LAN ports. How do I setup IPv4 software bridge using PFSense so that the rest of ports act as a network switch?
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Fedora Linux 20: Install Broadcom-wl STA BCM43228 Wireless Driver

I‘m using Dell / Lenovo laptop with Broadcom’s IEEE 802.11a/b/g/n based wireless card. How can I install Broadcom-wl STA BCM4322 Wireless driver on a Fedora Linux version 20?
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OS X: Create and use Live USB Fedora Linux Media

My new Dell Laptop has no DVD or CD drive. I’m trying to create a bootable Fedora Linux 20 USB using UNetbootin utility as described here. But, UNetbootin failed to create bootable USB image on OS X. How do I create Fedora Linux 20 USB Media in Apple OS X using command line options?
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HowTo: Upgrade To a Newer Version of Ubuntu 14.04 LTS

Ubuntu Linux version 14.04 LTS has been released. How do I upgrade to a newer version of Ubuntu 14.04 LTS from Ubuntu 13.10 or 12.04 LTS?
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X11 forwarding request failed on channel 0 Error and Solution

I am a new Linux server user. I need to tunnel X over ssh. I type the following command from OS X Unix terminal to login into far_away_machine (a centos server):

ssh -X -o options -A -p 22 user@centos-far-away-server

But, I am getting the following error on screen:

X11 forwarding request failed on channel 0
Last login: Sun Mar 23 15:58:51 2014 from 1.2.3.4

How do I fix “X11 forwarding request failed on channel 0” on Linux or Unix-like systems?
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Increase NFS Client Mount Point Security For a Web-Server noexec, nosuid, nodev Options

I am using NFS server version 4.x on a CentOS/RHEL based system. I’m mounting my shared /var/www/ directory on five Apache based nodes using the following syntax:

mount -t nfs4 -o rw,intr,hard,proto=tcp rocknas02:/httproot/www /var/www/

I noticed that due to bug in my app user can sometime upload executable or other device files to get out of chrooted Apache server. How can I prevent such security issues on a CentOS or RHEL based NFS client and sever setup?
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Unix / Linux: Check New Files In File System /var/www/uploads/

Recently, I switched from MS-Windows based web-server to CentOS Linux based Apache web-server. All user uploaded files are stored in /var/www/uploads/ directory. Is there command that can give me a list of files that have been added to the filesystem at /var/www/uploads/ in last 7 days on Linux/Unix-like oses?
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