You can read lots of posts about this issue but there is not much information about why this is the case or how grub determines the root= device name. Some even suggest modifying grub.cfg manually which is a disaster as the next kernel update will cause grub to revert back to the device name.
For most people this won't be an issue but those using template system, automated deployments and working in embedded may run into this issue with custom embedded and created minimal kernel........
The Best Docker Tutorial for Beginners
We quickly explain the basic Docker concepts and show you how to do the most common tasks from starting your first container, to making custom images, a Docker Swarm Cluster Tutorial, docker compose and Docker buildfiles.........
1. Let's work from an environment where we can install Ansible on.
If you are using an older version of Linux based on Mint 18 or Ubuntu 16, you may want to get the PPA and get the latest version of Ansible that way:
sudo apt install gpg
sudo add-apt-repository ppa:ansible/ansible
sudo apt update........
If you've come here, don't be embarraassed, working in IT, this is the MOST common computer problem that almost everyone will encounter. The reason why I'm doing this post is because I've seen an increase from colleagues and admins having this problem and many times it's not even your fault. A common scenario is that someone acquires a new or used computer which they weren't given the password for. Fortunately Ihave a detailed list of all the options whether free or pa........
This is especially helpful if you run your own servers. If you are presented with an error message or warning that the signature has changed or does not match the IP/domain you are connecting to you always want to verify manually.
So your e-mail/web client will show you an SHA-1 fingerprint like this:
"Could not verify this certificate because the issuer is unkown" or other reasons such as a mismatch in IP/domain.
It will also show you........
The solution is simply "tidy"/Tidy-HTML. It will take your poorly formatted HTML code (and I mean files that span just a few lines that are unreadable) and fix it up.
Note the command below does everything in place. *Make sure you take a backup of all .html files*
It also seems to break html5 code/templates so beware.
tidy -im yourfile.html
An automated way in bash:........
qemu-img create -b centos.5-8.x86.20120308.qcow2 -f qcow2 ../kvmguests/25000-centos5.8x86.qcow2
Formatting '../kvmguests/25000-centos5.8x86.qcow2', fmt=qcow2, backing_file=centos.5-8.x86.20120308.qcow2, size=10485760 kB
-b the source/base image
-f format is qcow2 and the location of the destination image
What is so special about this? It's even quicker than creating a template with OpenVZ but this is an actual OS.
It saves time a........
I don't expect this to be solved soon but some of Yahoo's DNS servers are out of whack. I changed the IPs of some nameservers of some domains and now most Yahoo users can't e-mail to those domains!
As you can see below by the "No MX or A records for mychangedomain.com", now Yahoo's DNS/mailserver DNS cache is wrong. You would think they would at least have cached the old incorrect records, but instead for some reason their DNS cache has no entry and doesn't seem........
One of the purposes of rsync is to backup whole filesystems and archive them but how can you do that properly and restore things to normal if all permissions and ownerships are not preserved from your root filesystem?
It's not desirable to have everything running as root, especially not just for an rsync.
The Easy rsync preserve permission solution for non-root users
sudo is the answer and all you have to do is edit /etc/sudoers
At the end o........
I decided on using yum to help me decide even though I normaly use proftpd I decided to see what else I could find.
yum search ftp
Loaded plugins: fastestmirror
Loading mirror speeds from cached hostfile
* rpmforge: ftp-stud.fht-esslingen.de
* base: mirrors.netdna.com
* updates: updates.interworx.info
* addons: yum.singlehop.com
* extras: mirrors.netdna.com
rpmforge........
Bash Script Infohttp://www.faqs.org/docs/Linux-HOWTO/Bash-Prog-Intro-HOWTO.html#ss10.5
http://www.scit.wlv.ac.uk/~jphb/spos/notes/shell/shell5.html
http://quong.best.vwh.net/shellin20/#LtohTOCentry-41
http://www.cactus.org/~dak/shellscript.html
http://db.ilug-bom.org.in/Documentation/abs-guide/
http://pegasus.rutgers.edu/~elflord/unix/bash-tute.html
http://heather.cs.ucdavis.edu/~matloff/UnixAndC/Unix/CShellII.html
Since bash i........
There's a lot of outdated information and confusion for system administrator's out there.
One annoying task for many an Administrator has been backing up data in Linux. You don't need any GUI tools such as K3B or GnomeBaker. Both are excellent tools but for veteran command line users working remotely, using the keyboard is a great and possibly automated way to save yourself pain and hassle.
At a later date we'll cover how scripting can automatically backup certain........