Will nobody think about the WAN/MAN
DC 5 nines are all good, but when you work with end user availbility in a global enviroment 5 nines is a whole new ball of wax, there are many obstacles to overcome before a user in a site could be given a garuentee of any figure.
How many ISPs opperate in each country? if only one then oh dear hold on to your ankles at your next SR
Which ISP owns the infra if running with multiple ISPs for sepracy?
How much influence do you have on SIP's after major outages affecting ISP's?
if running dual links, where does you ISP consider the last mile for convergence to be? No good if 5km from site and copper gets dug up by poor people and all your links go down including RF
Will your landlord let you add a new server room and seperate LAN in your location should you feel the need?
What is the local break fix support SLA's? do you have 4 hour resolution times for H/W failures, Desktops, Network, File Print?
Are spares easily avaialble to swap out in less then 4 hours?
How much revenue would you lose as a site if you do not get Five 9's? is this less than to cost of implementing? Do you want to spend €1m to protect €250k in losses over 3 years.
Who will fund these improvements? if you opperate in an Empire enviroment dominated by P&L never an easy question to answer
Is the user base running low attrition? is knowledge retained on Incident management, Business continuity management
is the user base well trainined? as above
Back at the DC
If the market has not provided an off the shelf solution and you A-team yourself a new one, will the original vendor(s) still support the core of their product you have not ripped apart to deliver the business what it needs
has the business given you a forecast of business for capacity planning?
just my thoughts.
As i say to my business partners off the record, you can have what ever you like just give me explicit and clear requirements, a blank cheque to deliver and run it inc for undocumented features, a well trained user base, good communication matrixs with named people to own it and review it, good SOP's owned and reviewed inc DR and BCP. A heads up on pipeline of volumes inc users, a pipeline of SIP and funding to implement
PS IT tries it's best to deliver world class service more so than other service providors like Finance, HR etc