Unix Revolution

When writing scripts,I often like to insert text into a file at a very specific location/line. The following lines of code, will enable rsync comment out the line starting with default_password_crypted insert a new line with  default_password_crypted in it's place [root@rhnsat01 ~]# sed -i -e 's/\=\ yes/\=\ no/g' /etc/xinetd.d/rsync [root@rhnsat01 ~]# sed -i -e 's/default_password_crypted:/#default_password_crypted:/g' /etc/cobbler/settings [root@rhnsat01 ~]# MYPASS=`openssl passwd -1 -salt 'Passw0rd' 'Passw0rd'` [root@rhnsat01 ~]# sed -i -e '84i'${MYPASS}'' /etc/cobbler/settings  In vi, to see the line you are on (I don't know how to turn the numbers back off though ;-) : set number

# cp /etc/ssh/sshd_config /etc/ssh/sshd_config-20120522 # sed -i -e 's/#PasswordAuthentication yes/PasswordAuthentication no/g' /etc/ssh/sshd_config # service sshd restart I guess when I set out to document this I thought the task was more challenging.  ;-) I went this route as I am sick of worrying about the script kiddies pounding on my system all day long.  I also scan the secure log every minute for random connection attempts and then shun them at my firewall.  I'll save that for another post.

I was rebuilding one of my lab boxes which has 4 x SATA drives (2 x 500GB and 2 x 1TB).  During the install I configured the Software RAID on the 2 x 500's for the OS, etc.. afterwards I wanted to use Software RAID to mirror the 2 x 1TB. 2 x 500GB - OS, swap, Virtual Machines 2 x 1TB - iSCSI and NFS share to be used by my RHEV 3 lab I acknowledged (just today) that GPT is the future... so I decided to use GPT to accomplish all of this. parted -s /dev/sdc -- mklabel gpt mkpart primary ext4 1 -1 set 1 raid on parted -s /dev/sdd -- mklabel gpt mkpart primary ext4 1 -1 set 1 raid on mdadm --create /dev/md127 --level=mirror --raid-devices=2 /dev/sdc1 /dev/sdd1 Conversely, if you are still using the MSDOS partition scheme (which is perfectly fine/normal for drives under 2TB), then the following would work also echo -e "o\nn\np\n1\n\n\nt\nfd\nw\n" | fdisk /dev/sdc echo -e "o\nn\np\n1\n\n\nt\nfd\nw\n" | fdisk /dev/sdd mdadm --create /dev/md127 --le...

I'm currently attempting to become more familiar with the iSCSI targets on Linux... so, I anticipate that I will be adding to this post - but what I have documented here should get a person by... # NOTE: I discovered this will not work on a VXFS mount if SELinux is enabled # :-( yum install iscsi-initiator-utils scsi-target-utils perl-Config-General mkdir -p /var/lib/tgtd/ lvcreate -L500g -nlv_tgtd vg_blackmesa mkfs.ext4 /dev/mapper/vg_blackmesa-lv_tgtd echo "/dev/mapper/vg_blackmesa-lv_tgtd   /var/lib/tgtd  ext4 defaults 0 0" >> /etc/fstab dd if=/dev/zero of=/var/lib/tgtd/iscsi-tgt-01.img bs=1m seek=100000 count=0 dd if=/dev/zero of=/var/lib/tgtd/iscsi-tgt-02.img bs=1m seek=100000 count=0 dd if=/dev/zero of=/var/lib/tgtd/iscsi-tgt-03.img bs=1m seek=100000 count=0 dd if=/dev/zero of=/var/lib/tgtd/iscsi-tgt-04.img bs=1m seek=100000 count=0 dd if=/dev/zero of=/var/lib/tgtd/iscsi-tgt-05.img bs=1m seek=100000 count=0 restorecon -RFvv /var/...

I have wondered what the difference, at a cursory level, was between the Workstation and Server version of the Red Hat flagship product. As you may have guessed, the Server product has a number of additional Server-based packages, and the same goes for the Workstation product. I did the following (I inserted the appropriate media in my machine) # ls /media/RHEL_6.2\ x86_64\ Disc\ 1/Packages/ > /tmp/RHEL_6.2-Workstation # ls /media/RHEL_6.2\ x86_64\ Disc\ 1/Packages/ > /tmp/RHEL_6.2-Server # sdiff /tmp/RHEL_6.2-Server /tmp/RHEL_6.2-Workstation | egrep '<|>' # sdiff /tmp/RHEL_6.2-Server /tmp/RHEL_6.2-Workstation | egrep '<|>' | wc -l 333 The "big 3" differences appears to be that Workstation includes OpenOffice, hyphen and Evolution.  Server includes cluster, and misc infrastructure type products.

Update : Unless you are playing games or something, I see no reason to use the Nvidia drivers.  After I installed the Nvidia drivers the external display was not auto-detected and required a restart of Gnome-shell to recognize the updated config.  Once I did that, it started in Gnome-fallback mode?  Bummer...  So - nouveau is the better option... IMO. I had decided to put Fedora 16 back on my rig.  I know this install won't be on this machine long as it has some quirky issues (sudden desktop lockups, WLAN occasionally flakes out, etc... I digress...)  I also decided to try the Nvidia proprietary driver, along with using the discrete Nvidia graphics chipset. So - the process was fairly straight-forward. # yum -y update # rpm -Uvh http://download1.rpmfusion.org/free/fedora/rpmfusion-free-release-stable.noarch.rpm # rpm -Uvh http://download1.rpmfusion.org/nonfree/fedora/rpmfusion-nonfree-release-stable.noarch.rpm # yum install akmod-nvidia xorg-x...

Issue :  Xmms is the only media player that I am currently able to configure to play mp3s.  So.. what I have done, is to install a Fedora 16 VM and run banshee with my RHEL ~/Music directory NFS mounted in my VM.  Banshee is where I manage my playlists, etc..  My logout script then copies the banshee.db to my ~/Music directory (as opposed to .config/banshee-1/banshee.db) I then run the following script to create a "default" Xmms playlist. I replace the default XMMS .m3u file, then I create a ~/Music/xmms.pls file (optional to use). Resolution : [jradtke@neo bin]$ cat banshee-to-xmms.sh  #!/bin/bash BANSHEEMINRATING=3 BANSHEEDBFILE=~/Music/banshee.db TMPSYNC=/tmp/banshee2xmms.tmp PLSOUT=~/Music/xmms.pls echo "select Uri from CoreTracks where rating > ${BANSHEEMINRATING};" | sqlite3 $BANSHEEDBFILE > ${TMPSYNC} sed -i -e 's/file:\/\///g' ${TMPSYNC} # MORE GENERIC FILE CLEANUP TYPE STUFF # THEN... REPLACE/REMOVE SOME OF ...