Calculating network availability?

[Skeng]

Hi,

I'm struggling with my assignment I have to work out the downtime for the (year,month,week and day). I've been looking around online for the formula to work it out but every site I find assumes the network will be running 24 hours per day.

Here are the "specs"

12 hours per day 7 days per week at 99.999% availability.

Can anyone tell me the formal to work this out.

regards -Skeng

 

[SMN]

http://easyuptimecalc.com/index.php is a good site.

Uptime: 29 days 23 hours 59 minutes 34 seconds
Downtime: 25 seconds
Percentage uptime: 99.999%

 

[GhostlyPea]

Ignoring the fact that in the real world it's 24/7

Surely it's just 12 x 7 x 365 = hours in a year. Multiply this by 60 and then 60 again gives you seconds in a year. Then take the number of seconds the device was down for and divide this number by the original total?

i.e. a device was down for 5 minute

50 minutes = 3000 seconds

Time in year on a 12 hour day = 110376000

110376000 - 3000 = 110373000

110373000 / 110376000 = 0.9999728201%

Simple maths =/ (unless I got it wrong then I look stupid)

- GP

 

[bremen1874]

Surely it's just 12 x 7 x 365 = hours in a year.

Or not

I recon

1 day = 43200 seconds (60 x 60 x 12) permitted downtime = 0.432 seconds (0.001% downtime).
1 week = 302400 seconds (60 x 60 x 12 x 7) permitted downtime = 3.024 seconds.
etc.

 

[GhostlyPea]

Or not

I recon

1 day = 43200 seconds (60 x 60 x 12) permitted downtime = 0.432 seconds (0.001% downtime).
1 week = 302400 seconds (60 x 60 x 12 x 7) permitted downtime = 3.024 seconds.
etc.

Man my maths is terrible Just got out of a 4 hpour meeting in a room thats far too hot!

Should be corrected: 15721800/15724800 = 999809

Any better

- GP