Create an account Home  ·  Topics  ·  Downloads  ·  Your Account  ·  Submit News  ·  Top 10  
· Home
· Content
· Feedback
· News
· Search
· Statistics
· Surveys
· Top
· Topics
· Web Links
· Your_Account


The five ITIL books can be obtained directly from the publisher's website:

Or as downloadable PDFs: HERE

Current Membership

Latest: tamikafu3
New Today: 32
New Yesterday: 42
Overall: 231786

People Online:
Visitors: 141
Members: 1
Total: 142 .



Don't have an account yet? You can create one. As a registered user you have some advantages like theme manager, comments configuration and post comments with your name.

Related Resources

Service related resources
Service Level Agreement

How to set up
IT Change Management
Process Info-Graphic

NOTE: ģ ITIL is a registered trademark of OGC. This portal is totally independent and is in no way related to them. See our Feedback Page for more information.


Select Interface Language:

Please contact us via the feedback page to discuss advertising rates.

The Itil Community Forum: Forums

ITIL :: View topic - Availability Questions
 Forum FAQForum FAQ   SearchSearch   UsergroupsUsergroups   ProfileProfile   Log in to check your private messagesLog in to check your private messages   Log inLog in 

Availability Questions

Post new topic   Reply to topic    ITIL Forum Index -> Miscellaneous
View previous topic :: View next topic  
Author Message

Joined: May 10, 2007
Posts: 6

PostPosted: Fri Sep 07, 2007 10:24 pm    Post subject: Availability Questions Reply with quote

We are in the middle of trying to determine how to do Availability and I was wondering how other people do theirs. The biggest discussion so far is around when to take an availability hit or how much of a hit to take when part of the service is not working. There is no list of critical business functions for each service and IT is going by what they think are critical business functions vs getting those from the business. My thoughts were determine critical business functions and as a whole they make up availability for the service. If one of those critical business functions is unavailable you would take an availability hit equal to the importance of the function. Any feedback on how you handle Availability would be great!
Back to top
View user's profile
Senior Itiler

Joined: Oct 13, 2006
Posts: 116
Location: South Africa

PostPosted: Wed Sep 12, 2007 12:53 am    Post subject: Reply with quote


Availability Management is one of the disciplines companies tend to deal with "last". And many do not progress beyond component availability (e.g. "SAP server 1 was 99.7% available last month").

When you deal with end-to-end service availability you have to consider how to average over multiple end-users. If one site out of 10 went down for 1% of the month, that's only a 0.1% hit on availability, ie 99.9% availability. (Assuming all the sites had the same number of users. The same number and profile of users, even.)

But you were asking about multiple features within the service. I think you should identify CBFs in partnership with the users - but when you look at availability, only worry about the ones that are likely to fail independently, and which you can actually measure.

Then you'll need to weight the features. If they don't rely on each other you could have CBF1 = 40%, CBF2 = 40% and remaining features = 20% - again, agree this with the users. The availability figures have to be meaningful to them.

On the other hand if they can't do anything without CBF1, then a failure of CBF1 is a 100% hit - 0% availability for the duration.

Also bear in mind time factors - if the service is only used during office hours, don't report availability for other hours. Consider critical business periods e.g. month end, and be prepared to report on bad cases - a day with ten 5-minute outages will definitely be remembered by the users even if your availability for the month is 99.5%.
Back to top
View user's profile Visit poster's website
Senior Itiler

Joined: Apr 26, 2005
Posts: 57

PostPosted: Tue Oct 16, 2007 10:45 am    Post subject: Reply with quote

Hi, I agree with JoePearson, and I would like to add another point.

Once you have identified your CBFs, you also need to determine all the components that make up the service and determine their importance. Some equipment could have failover or redundancy built in. You need to identify all of these components, and gather the total cost of maintaining that service at that level. This information is then used in your reports back to the business. It is these hard numbers of both the availability and cost that will give you support when the business want better availability. You can tell them it will cost an additional $xxxxx, for an increase of x.xx% in availability. Using the combination of these numbers is very convincing when presented to the business.

Availability is something that most people donít care about, until it is not there. Wink

Azard Omardeen
ITIL Expert / Accredited Trainer / ITSM Consultant
Back to top
View user's profile Send e-mail
Display posts from previous:   
Post new topic   Reply to topic    ITIL Forum Index -> Miscellaneous All times are GMT + 10 Hours
Page 1 of 1

Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

Powered by phpBB 2.0.8 © 2001 phpBB Group
phpBB port v2.1 based on Tom Nitzschner's phpbb2.0.6 upgraded to phpBB 2.0.4 standalone was developed and tested by:
ArtificialIntel, ChatServ, mikem,
sixonetonoffun and Paul Laudanski (aka Zhen-Xjell).

Version 2.1 by Nuke Cops © 2003

Forums ©


Logos/trademarks property of respective owner. Comments property of poster. Rest © 2004 Itil Community for Service Management & Foundation Certification. SV
Site source copyright (c)2003, and is Free Software under the GNU / GPL licence. All Rights Are Reserved.