In the past few days my Postfix server has been having occasional problems talking to the mail gateway. They problem would come and go. The Postfix server would timeout trying to connect to the gateway and keep …
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Here is a quick example showing how to count users logged in on a particular date using the “last” command on Linux.
A sample process for moving a user to a new primary home group on Solaris.
In a major announcement from Dell yesterday, the company announced that its public cloud ecosystem and strategy will be centered on partners Joyent, ScaleMatrix and ZeroLag, and will emphasize recent acquisition Enstratius. The announcement represents …
Over at the Washington Post, Jason Samenow writes that an infusion of funding into the National Weather Service from Hurricane Sandy relief legislation promises to facilitate massive upgrades to key supercomputers, dramatically improving local, national, …
Google and NASA have teamed up to launch a new laboratory focused on advancing machine learning. The Quantum Artificial Intelligence Lab — hosted at NASA’s Ames Research Center in California — will contain a quantum …
Your cloud provider is great. Your cloud provider is cheap. Your cloud provider is out of business.
Now what do you do
If your favorite consumer cloud service goes out of business or simply feels it’s time …
It’s a testament to Linux’s ubiquity and versatility today that so many “best of” lists are published focusing on the free and open source operating system.
Just in the past few months here on Linux.com, for …
The rpc.statd service is used by NFS client to help it recover from loss of connectivity to the NFS server. When rpc.statd is not running, NFS is not able to handle remote file locking. You …
Changing hostname and IP is frequently required when a server is being moved from testing or development to production. The process is a fairly simple one, but steps must be performed in a certain order to avoid complications.
In the past few days my Postfix server has been having occasional problems talking to the mail gateway. They problem would come and go. The Postfix server would timeout trying to connect to the gateway and keep …
Pflogsumm is yet another log analyzer/summarizer for Postfix. It is written in Perl and has been around for a while. Very simple to install, so I writing this post mostly as a note to myself. …
Below is a simple script to test filesystem read/write performance using dd with varying blocksize parameter. This can be useful for testing local filesystems as well as network-mounted filesystems. The end result will be a …
The recent announcement from Suse Enterprise Linux that Btrfs was production-ready raised some suspicions. The last time I tested btrfs (not very long ago) the primary issues were excessive CPU utilization and filesystem space that seemed to disappear into nowhere. So, as a quick test, I put together an OpenSuse 12.2 (3.4.6-2.10-desktop, OpenSuse 12.2) 64-bit VM (ESX) with one dual-core vCPUs, 4GB RAM, the OS disk and a 6GB striped LVM filesystem consisting of 4 4-GB virtual disks.
After years working with PBS and LSF, ran into Jeff Layton’s “Share the Load” review of openlava resource manager in the Feb 2013 issue of the Admin Magazine and nostalgia took over. So I built …
Below is a simple script to test filesystem read/write performance using dd with varying blocksize parameter. This can be useful for testing local filesystems as well as network-mounted filesystems. The end result will be a …
Imagine you have an HPC cluster with a hundred compute nodes named node001-node100. The two commands below will help you generate a list of node names – either all name on one line or one name per …
Just a simple script to scan an IP range and do a reverse DNS lookup. This can be useful for building an inventory of systems on your LAN. Just make sure to give your network …
Igor
Sr. Unix SysAdmin with fifteen years experience supporting Solaris, HP-UX, AIX, IRIX, and Linux servers in a large distributed environment.
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