Author Archives: rhosto

So many to choose from.

For the last month or so. There has been a debate amongst, my peers and I, on which is the better file system on Linux and how to benchmark and test it. So digging through my back log of emails I notice that Linux Magazine was running a series on the this some topic. So I thought I would sure.

Lies, Damn Lies and File System Benchmarks

Metadata Performance of Four Linux File Systems

Metadata Performance Exploration Part 2: XFS, JFS, ReiserFS, ext2, and Reiser4

Reinstalling the Boot Loader on RHEL

In many cases, the GRUB boot loader can mistakenly be deleted, corrupted, or replaced by other operating systems.

The following steps detail the process on how GRUB is reinstalled on the master boot record:

  1. Boot the system from an installation boot medium.
  2. Type linux rescue at the installation boot prompt to enter the rescue environment site link.
  3. Type chroot /mnt/sysimage to mount the root partition.
  4. Type /sbin/grub-install /dev/hda to reinstall the GRUB boot loader, where /dev/hda is the boot partition.
  5. Review the /boot/grub/grub.conf file, as additional entries may be needed for GRUB to control additional operating systems.
  6. Reboot the system.

Cloud computing

Cloud computing is a style of computing in which dynamically scalable and often virtualized resources are provided as a service over the Internet.
Cloud computing can be confused with:

  1. grid computing—”a form of distributed computing whereby a ‘super and virtual computer’ is composed of a cluster of networked, loosely coupled computers, acting in concert to perform very large tasks”;
  2. utility computing—the “packaging of computing resources, such as computation and storage, as a metered service similar to a traditional public utility such as electricity”;
  3. autonomic computing—”computer systems capable of self-management”.

MySQL Table Maintenance.

This morning I was asked by one of the other Engineers in my group about an easy way to analyze all the tables in a database. So I pointed him to mysqlcheck. Which is a great command line client for performing table mainteneance on mysql database tables. It checks, repairs, optimizes, or analyzes tables, all from the command line. Like any other program it has a ton of flags, but here are three general ways to invoke it.

shell> mysqlcheck [options] db_name [tables]
shell> mysqlcheck [options] –databases db_name1 [db_name2 db_name3…]
shell> mysqlcheck [options] –all-databases

For more information check out.

MySQL 5.0 Reference Manual :: 4 MySQL Programs :: 4.5 MySQL Client Programs :: 4.5.3 mysqlcheck — A Table Maintenance Program

Unfreezing media in Netbackup on Solaris.

Here is something you don’t use everyday or at least I don’t. 🙂

First find the frozen media IDs.

shell>/usr/openv/netbackup/bin/goodies/available_media | grep FROZEN

A00060  HCART3   TLD      1       37     –       1     0        FROZEN
–snip–

Then unfreeze them with this command xenical otc.

shell> /usr/openv/netbackup/bin/admincmd/bpmedia -unfreeze -m A00060