Bandwidth calculation for Data Guard log shipping.

[raiq1]

Dear Erman sir,

Hope you are fine , currently we have a standby machine with data guard setup are already working. Now move to this server to different location.

We are trying to calculate how much bandwidth we'll need to keep a standby database updated using DataGuard.

Follow this note:-

 How To Calculate The Required Network Bandwidth Transfer Of Redo In Data Guard Environments (Doc ID 736755.1)

Here mentioned about Redo rate bytes per sec  , need to understand how we will get it redo rate per second.

Kindly guide us to exact calculate require for band width.

Regards,
Raiq

[ErmanArslansOracleBlog]

Formula is : Required bandwidth = ((Redo rate in Megabytes per sec. / 0.70) * 8)= bandwidth in Mbps

In that note, they just assumed that there is a conservative TCP/IP network overhead of 30%.. (so you can play with that 0.70 values accordingly.. *8 is required for byte to bit conversion, since we get Megabit per sec.

So you need to get your redo rate in Megabytes per sec (how much (in MB) redo you generate in a second,) and then you will be good with the formula.

You should get he highest value for the redo rate. I mean, you should calculate the bandwidth required according to the worst case scenario.

You can get it using v$SYSMETRIC_HISTORY. You can get the max value out of it.. (or you can just choose an average one)

Example:
select trunc(max(value)/1024*1024,1) "Max Redo MB Per Sec" from v$sysmetric_history where metric_name = 'Redo Generated Per Sec';

[raiq1]

Sir,

As per your query provided by me.

select trunc(max(value)/1024*1024,1) "Max Redo MB Per Sec" from v$sysmetric_history where metric_name = 'Redo Generated Per Sec';

output is : 605960.4

after that I put above output in the formula.

Required bandwidth = ((605960.4/0.70) * 8) =  6.925 bandwidth in mbps

can you confirm me , is it a right calculation .

Regards,
Raiq

[ErmanArslansOracleBlog]

You want me to verify the math? c'mon Raiq :) I already guided you on this.