Technology

Technology

Running multiple instances of MySQL with Solaris Coolstack 1.2

January 21, 2008 by 0 Comments

We recently had a requirement to run two instances of MySQL on two separate Solaris systems (for the purposes of dual-master replication). The systems in question were both SunFire T2000s running Solaris 10 (U3) and Coolstack 1.2 and already had a previous/single instance of MySQL running (SMF service csk-mysql).

In the end, it was a relatively straightforward exercise in that all we really did was replicate the existing instance (control script, configuration file and manifest file) and change the necessary bits of the resultant files so that the new instance was sufficiently different to the old, in the end, producing two independent SMF services (csk-mysql1 and csk-mysql2). Specifically, the following files were created:

MySQL Control Scripts:
/opt/coolstack/lib/svc/method/svc-cskmysql1
/opt/coolstack/lib/svc/method/svc-cskmysql1

MySQL Configuration Files:
/etc/my1.cnf
/etc/my2.cnf

MySQL Manifest Files:
/var/svc/manifest/network/cskmysql1.xml
/var/svc/manifest/network/cskmysql2.xml

The manifest files were identical but for the name of the service and the control script they invoke. The control scripts were also identical but for the configuration file and DBDIR that they use and the difference(s) in the configuration files were mainly in terms of the port numbers and socket files used.

Beware

The only thing that caught us out was in modifying the control scripts (to tell them which configuration file they should use). This was done by adding a --defaults-file argument to the invocation of mysql_safe. However, you need to ensure that this argument is the first one you pass to mysql_safe. Otherwise, MySQL will launch will not load the correct configuration settings. This is not (well) documented so beware!

Also, when trying to access the new instances via the mysql client, you will need to add the -P and -S arguments.

Technology

Renaming a Solaris system

January 20, 2008 by 0 Comments

I’ve had to change the hostname of a number of Solaris systems over the past few weeks, some of which were (sparse) Solaris zones. Here are some notes for my/your future reference:

File Global Zones Non-Global Zones
/etc/nodename Yes Yes
/etc/hostname.ifname Yes No
/etc/hosts Yes Yes
/etc/inet/hosts Yes Yes
/etc/inet/ipnodes Yes Yes

Notes

  1. You will need to replace the ifname above with the name of the appropriate interface on your system.
  2. Depending on your system configuration, I may of course be missing some files. However, the above worked for me!
  3. None of the systems in question were running IPv6
Technology

Uninstalling Sun Studio

January 16, 2008 by 1 Comment

I recently had reason to upgrade to a newer version of Sun Studio on a Solaris 10 system. I had Studio 11 installed but needed to go to version 12 for better support of natively compiled Ruby Gem packages (e.g. mongrel). However, uninstalling Sun Studio is not the most readily documented thing in the world so, for my own future reference, here is the easiest way to do it:

# cd /var/sadm/prod/com.sun.studio_11
# ./batch_uninstall_all

After this, just follow the on-screen instructions …

Technology

Native Ruby Gems require Sun Studio 12 with CoolStack 1.2

December 6, 2007 by 0 Comments

A substantial number of Ruby Gem packages are written in Ruby itself and install quite neatly using a simple gem install command. However, a number of Gem packages are partly written in C and require some compilation during installation (e.g. hpricot, fastthread and mongrel). This requires you to have a C compiler on the system where you are installing the packages, which is a real pain, but that’s a gripe for another day.

We recently upgraded to CoolStack 1.2 but when we tried to install the Gem packages above, we ran into trouble when the installer attempted to compile the native code for the package. The compiler (Sun Studio 11) complained about the definition of the NORETURN macro in /opt/coolstack/lib/ruby/1.8/i386-solaris2.10/config.h as follows:

syntax error before or at: __attribute__
warning: old-style declaration or incorrect type for:
__attribute__
warning: syntax error: empty declaration
...
cc: acomp failed for hpricot_scan.c

It turns out that the new version of Ruby (1.8.6) that is included with CoolStack 1.2 contains some GCC-oriented macro definitions that Sun Studio 11 does not support. The solution was to upgrade to Studio 12.

Huge thanks go to Basantk for helping to resolve this.

Technology

Q&A Session with Bruce Schneier

December 5, 2007 by 0 Comments

For those of you who that have not heard of Bruce Schneier, he is an world renowned cryptographer and computer security specialist and has authored loads of books on these subjects.

This recent Questions & Answers Session with Freakonomics makes for fascinating reading, even to the most basic of computer users. All of the questions were created by subscribers to the Freakonomics Blog over the course of the previous week.

Source: SlashDot

Multimedia

Internet Marketing piece on Today FM’s Last Word

October 12, 2007 by 0 Comments

There was brief, non-technical discussion on Internet Marketing on The Last Word programme on Ireland’s Today FM radio yesterday. They do pieces like this from time to time and they’re generally quite informative to the uninitiated listener.

This discussion was targeted at those whose core business is marketing and selling via the Internet and how to understand (and possibly improve) the search ranking being achieved by your website.

The interview starts at around 31 minutes into the Podcast of Thursday’s Last Word radio programme.

Technology

Aren’t Mothers Great

October 12, 2007 by 0 Comments

The mother of a 13-year old girl gives Steve Ballmer from Microsoft an earful about her experiences with Windows Vista, their latest operating system offering.

I especially love how she appeared to got the final word in when, after Ballmer tried to waffle his way around the situation suggesting the Service Pack 1 would address many of the issues she’d seen, she retorted, “Good, I’ll let you come and install it for me!”

Priceless!

Source: SlashDot

Technology

Interesting Map of the Internet

October 8, 2007 by 0 Comments

Chris Harrison, a doctoral student from Carnegie Mellon University’s Human-Computer Interaction Institute has produced a series of interesting maps depicting the geographical structure and distribution of the Internet.

Here are some interesting observations I made:

  1. The coverage in the southern hemisphere is surprisingly low
  2. The coverage in India and (to a lesser extent) China is much lower than I expected
  3. The coverage in Australia reflects the location of most of the major cities in the south-eastern region of the country.
  4. Less well-developed continents like Africa and South America have poor coverage
  5. Whilst Ireland seems to fare reasonably well in Europe, if you zoom in on Ireland, you could argue that Waterford appears to be among the least well-served.

What do you think?

Source: SlashDot

Technology

Installing Solaris 10 x86 in VMware

September 28, 2007 by 0 Comments

I installed Solaris 10 x86 in a VMware Virtual Machine on a laptop earlier this week. It was mostly a straightforward process as I’d used VMware before to install Ubuntu Linux on a number of desktop systems. However, I did run into some trouble on the networking front.

The Problem

Whenever I generated a large amount of network traffic (i.e. copy a 300MB file onto it), the network driver (pcn0) seemed to fall over and die, rendering the VM unreachable from the outside world. I was using the SSH copy tool (scp) tool to carry out the file copy and the problem manifested itself by causing scp to report that the copy was stalled – a state from which it never returned. When I investigated from the system console, the pcn0 interface no longer had an IP address (but was still up). I had to reboot the VM to recover from this.

The Solution

In the end, the solution was to install VMware Tools which actually installs a different network driver (vmxnet) in place of the pcn driver. After VMware Tools was installed I did have to manually rename some of the networking files in /etc (hostname.pcn0 to hostname.vmxnet0 and dhcp.pcn0 to dhcp.vmxnet0) to get the system back on the network. But once I did that (and rebooted), every worked fine and I haven’t had any problems since.
If you happen to have a DVD/CD mounted in the VM (either physically or via ISO image), you should unmount if before attempting the VMware Tools installation as this process tries to mount an ISO image as part of the installation. If you fail to do this, the VMware Tools installation process will pretty much just sit there and give you no feedback as to what’s happening. Despite this, I am still a big fan of VMware and of Solaris.

I used Solaris 10 U3 (10/06) and VMware Server for Windows 1.0.3 Build 44356.