Archive for May 2009
Linux growing partitions on the fly with blockdev(1)
One thing I wished that Linux could do was to dynamically grow a partition online. This is something I was accustom to in HP-UX, AIX and even Solaris. It’s a pretty common operation to do in an enterprise environment with SAN LUNs. Lets say I have a web server running Apache on Linux. The htdocs dir sits on a dedicated SAN LUN and is slowly filling up. This server is a production box. Everything is using LVM. Before we can expand the FS, LV, or even the VG we need to grow the physical parition that the VG lives on. We expand the physical LUN size on the SAN, and fdisk the partition in Linux but linux still does not see the updated partition table size (without a reboot) – this is not good!
However, do not fear! I come across the very command to address this problem: blockdev –rereadpt /dev/sdX
Sigh… I wish I came across this command years ago!
DMT tool for Speedtouch
I’ve just come across this awesome little utility called “DMT” for Speedtouch and similar routers. Speedtouch routers have a telnet interface that let you access a fairly powerful command line interface. You can configure advanced aspects such as IDS, SNMP, etc. DMT is essentially a GUI to the telnet interface providing a complete (and awesome) overview to your Speedtouch router. Checkout the screenshot below.
DMT can be downloaded from http://www.kitz.co.uk/routers/DMTv7.htm
