≡ Menu

Intermediate

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?
[click to continue…]

{ 3 comments }

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?
[click to continue…]

{ 48 comments }

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?
[click to continue…]

{ 8 comments }

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?
[click to continue…]

{ 0 comments }

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?
[click to continue…]

{ 6 comments }

CentOS / RHEL: Yum Lock Package Version At a Particular Version

I am a new CentOS / RHEL 6.x server user and DevOP. I need to lock a package called nginx on a server being updated via yum command. How do I lock package version at a particular version on CentOS / Red Hat Enterprise Linux (RHEL) 6.x or Fedora Linux?
[click to continue…]

{ 10 comments }

Mac OS X: Install wget Network Downloader Utility

I recently learned that “wget” can continue getting a partially-downloaded (resume download) file. I am unable to find wget command on Mac OS X. How do I install install wget on Mac OS X (Mountain Lion/ Mavericks / Snow Leopard)? How can I install wget in Mac OS X without 3rd-party repo such as Homebrew or MacPorts?
[click to continue…]

{ 11 comments }