Thursday, 10 May 2007

Finding extra space on a VMWare Virtual Machine

Now our Redgate SQL Server backup system is running nicely it has exposed a slight deficiency in my server setup over in Manchester, the problem now is that when I created virtual machines for all our little applications running on the VMware system I only gave then 4GB disks :o)

For the Nagios system, the Intranet applications, the source code repository and the knowledgebase these disks are perfectly adequate but for database backup obviously a bit more space is required. Having utilised a spare folder on the knowledgebase virtual server for the SQL Backup it would have been very inconvenient to erase the machine and create a new one and also given the fact that the host server is not overburdened with RAM I didn't feel it would be wise to put more than 4 machines on the system.

So we come to a less well documented feature of a VMWare virtual machine, when you set the hard disk size on creating the machine you cannot increase it in the future. So you have 2 choices, the Lego approach - smash it up and start again, or the clever approach, add on a new virtual disk. I chose to be clever and in a nice twist of fate got away with it :o)

So I think a little how-to is in order.

Begin by adding a new disk in VMWare, it was recommended that I choose a SCSI disk so I complied, bear in mind this has to be done with the virtual machine powered down. When you have added the disk just power up again and you are there, all you have to do now is to get your Linux install to make use of it.

As I have blogged before our flavour of choice when it comes to Linux is CentOS but RHEL4 or Fedora would probably work in exactly the same way because its pretty basic stuff really.

First use Fdisk to create a new partition, as this is our second disk its SDB (SCSI Disk B)
fdisk sbd
and then just follow the instructions to create a new partition.

Next you need to format the new disk so:
mkfs.ext2 /dev/sdb

At this point you need to check the space on the disk so:
and you should see your new disk listed

Finally you need to mount the disk so:
mount -t ext2 /dev/sdb /home/samba/sql

As I was using samba to share the /home/samba folder all I needed to do was update the permissions on the folder and restart the service - job done.

Now I have a bit more space on the share the backup has worked a treat, it is one of the real strengths of the Red Gate system that you can see immediately how your backup routine is performing using the timeline GUI. As you can see from the picture here the first couple of databases backed up nicely but given that they are larger databases they are a bit snug so I might just ease them apart a little so we don't get a clash as they grow.

Tuesday, 1 May 2007

SQL bakcup - a can of worms!

It seems that the SQL Backup market place is far busier and competitive than I had imagined, no sooner had I arrived in the office this morning than a nice person from Quest Software, makers of Lite Speed, finally caught up with me and set me right on the technology and the price. It seems they have a very interesting suite of SQL server products all of which make the standard Microsoft tools easier to use and in some cases adding functionality, the version I had seen yesterday happened to be the developer version at $45, a full version for our setup being £700 - a bit of a jump. In the end I spoke to 3 people there and came away with a whole heap of good advice and technical background to the product.

No sooner had I finished on the phone than I had a very pleasant representative from Red-Gate, makers of SQL Backup, on the phone wanting to discuss my recent blog post (Gulp!). Actually it turns out that instead of wanting to sue me for mentioning their software on my rather random blog he wanted to give me a full pitch for the product and was very happy to offer a cheeky discount, a good deal on support and some very good advice about which product was right for us. It also turns out that I was already out of date as version 5 had come out over night and I am just in the process of kicking that around. The benchmark looks about the same, maybe a slight improvement in performance, but it has a rather nifty new GUI which plots your backup activity on a time line graphic so you can visually see whether your backup schedules are in danger of overlapping and going into a shame spiral. (Cue - dip into Google images for shame spiral and discovering a picture which is also fitting for the genius which is the time line GUI).

My next step was to download a trial of HyperBac to evaluate their approach which shuns the extended stored procedures of the other products in favour of a totally stand alone setup for SQL backup. This in turn invited another phone conversation as I actually gave my real phone number when downloading :o) It seems the nice people who created HyperBac where originally involved with creating Lite Speed and they decided to create a new company with a new approach a while ago. Again their sales dude was a wealth of information about the strengths and weaknesses of the various approaches taken and was very helpful indeed. The cost for our setup was $499 irrespective of the number of processors we wanted to throw at it and as such it sits directly between the other 2 products. Having played with the system it performs well but I would say that both Xceleon and Quest will be interested to have a good squint at SQL Backup version 5 as they are both slightly quicker but overall I think Red-Gate have it.

I have set our demo rig up for hourly backups overnight so I will be interested to see what is waiting for me by the time I get in tomorrow morning! Hopefully a useful archive of backups which all restore perfectly.... we'll see :o)

A view from the rack is the personal blog of an IT manager who works for a pub company - hence beer