Posts Tagged ‘backup window’

Online backup seed installation

Tuesday, September 23rd, 2008

Online backup seed installation.

The word installation above could be misleading but is included because of its’ common and accepted usage when detailing the “backup to disk” function which  comes with all quality online backup systems. Backup to disk can actually be run at any time but here we are talking about the initial backup post installation.

A seed install is effectively an installation for which the first backup is run locally. There are a number of reasons for which this may be the chosen first backup method. Most equate to broadband, time, data quantity and backup window limitations. Lets take a closer look.

Broadband.

Commonly, download speeds are  significantly greater than upload speeds. In the main this is logical as web browsing involves far more download than upload and most web users general download more and more often than they upload. This offers advantages when restoring data online but the actual backup process which is the more common online backup communication direction uses upload. If your upload speed is low a seed install may be recommended.

Time

Your provider (and likely your software) can give a reasonably accurate estimate as to the amount of time the first backup will take. If you are depending on the online backup system before it has run in your environment for some time (not recommended) then the length of time between to initial backup starting and the next backup completing will be of much importance to you. If the first backup is going to take more time to run than a “backup to disk” and forwarding of same to your provider would take then a seed install may be the best choice.

Data quantity.

No matter how good your upload speed, if the data quantity is inordinately large it will take considerable time over broadband thus making the seed install an attractive option. It must be remembered that companies with enviable upload speeds commonly have significant quantities of data so upload speed advantages are often negated by excessive data quantities.

Backup window.

Your backup window is the length of time a backup has to complete to allow for user access,  application access and next scheduled backup. Seed installs are commonly used to beat the backup window deadline. In these cases it is standard practice for a technician to run the install on site and collect the data if it is to be at the data-store when the next backup starts.

There is one other area of consequence which was not listed above and that is the area of “technical issues”.

An acute example of this in computing is when a process with a progress indicator hangs on circa 99% of the completion indication. This is normally not a coincidence and usually a sign of an error, bug or fault anywhere in the system. If this equates to a significantly large first backup only it may be resolved by a seed backup but regardless the fault should be sought and rectified. Remember that any compromise on a large backup will likely be required in the instance of a large restore. 

In short. Seed installs are common. If a provider is running a seed install at your office, find out why. Many reasons are acceptable. If however, the reason is due to a system crash discuss this with the technician and see if the issue can be resolved so you do not run seed installs for the wrong reasons.

Remember that a crash may not be the fault of the technician. The online backup technician who arrived at your ofice for the first time today can not be responsible for technical issues which have been in existence visably or dormnant for some time. It could be due to a slow processor, a lack of RAM, a network issue or  your broadband. It is also important that if it is possible to rectify the issue for the technician that you  do this rather than run an unnecessary seed install.

Online backup agnosticism and the availability effect.

Monday, September 22nd, 2008

Online backup agnosticism and the availability effect.

All systems, even those which have proven themselves require a certain amount of faith. Your backup system which you have used, received reports from, ran test restores with and have been saved by is no exception. You leave the office tonight believing the backup will complete. The fact that you can verify this in the morning does not negate the faith requirement, it simply reduces the length of time for which this is a required. If an agnostic in the truest instance is someone who does not believe because the can not tell for sure then technical systems such as online backup are somewhat removed from this as the technology has been proven. Each backup can however be said to require a certain amount of faith on a per session basis as things can go wrong locally and globally.

An online backup skeptic (and they are I believe reducing as a percentage of the population) is not likely to employ online backup but there are many agnostics happily using the system. They are however the most likely to interfere with it. If you have little faith in your belt, you will employ braces. If you have little faith in your trousers staying up you will employ both. The consequence is that you must be aware of and take account of the effect one has on the other.

A good number of online backup users (and indeed users of any system) will employ braces also. This can come in many forms. In the example of online backup being the belt, the braces are often one or more of the following.

1. Tape backup; 2. External hard drive drag and drop; 3. Network drive; 4. Drive clone.

We as an online backup provider can not tell you to refrain from using any other system. As an outsource provider with responsibility for one specific area it would be irresponsible and risk inducing for everyone for us to give such advice. 

We can and do say the following.

All selected files should be available for backup during a backup session. The use of alternative systems in tandem should be managed to allow both systems to have unimpeded access to all of the files they are intending to backup. Any move away from this regardless of backup window constraints is a compromise which could have negative consequences.

Additionally, many backup systems mark files as backed up and any possibility of these files which are flagged as backed up by one system affecting the selection process of a tandem system must be understood and allowed for.

Aside from the already addressed and logical reasons for us not advising clients to refrain from using legacy systems there is one more (at least) good reason for this. That is that we are not altogether different!

Our own systems receive encrypted and compressed data from clients literally all the time and this is mirrored to secondary servers. None of this is surprising but what you may find surprising is this.

We shutdown mirror servers and clone drives. We can do this because the clients primary servers are available to accept backups and provide restore data and the mirror will continue when the mirror server goes back online.

We do this because despite our obvious belief in online backup as the best possible data backup system, we are agnostics on a per session basis with regard to any system. In conclusion, our agnosticism is another reason to have faith in us.