Opinions Wanted - Frequency vs. Calander based Scheds. 2

[Dorga]

I am trying to figure out which would work best for our environment, currently Frequency is failing and we are considering trying Calander.

Environment:
Pick an OS for the clients, we have it. several thousand.
Master & Media servers in question are all Solaris 8
4.5 DC MP4 (Also planning on switching to FP later on)
61 LTO drives on various L700's

Currently several policy's which are set to run from 7pm to 7am do not kick off until about 6:55am, then we get approx 2500 196's every morning.. not fun for those policy's..

So, in order to consider switching to Calander, im looking for the good, the bad, and the ugly reasons for staying with Frequency, or for switching to Calander.

 

[Stumpr]

7PM - 7AM = 12 hours
Set frequency to >12<13 hours
That should cause the jobs to be queued by 8PM

Large sites should avoid calendar based because of the personnel overhead required to maintain it.


Bob Stump
Incorrigible punster -- Do not incorrige

 

[comtec17]

Also the Calendar based scheduling is buggy as hell...

 

[PGPhantom]

Personal opinion (I accept no responsibility neither implied nor explicit in the result of opinions expressed henceforth .. ) Calendar based scheduling should be thrown doen the perverbial toilet so to speak - We do not use it and never will, until they fix it - Far too problematic.

Frequency scheduling is definitely the way to go and here is what we did:
Each Policy typically contains a "Full" and a "CINR" backup schedule. For the Full, I normally run them on Friday night to Saturday morning. The Window is set for 12 hours on Friday noght from 6:00 p.m. to 6:00 a.m. on Saturday morning. The frequency is once per day i.e. once per 24 hour period. Due to the window, the job will only ever run on Friday night and on schedule.

My cumulative incrementals are set to run nightly Saturday - Thursday from say 6:00 p.m. to the next morning at 4:00 a.m. i.e. A ten hour window. The frequency is set to once per 12 hours and I have never missed a backup with this.

 

[MrOttoX]

It all depends on your environment, your full knowledge of the two scheduling mechanisms and your overall scheduling strategy.
We had frequency based on most of our environments, and we changed them all to the Calendar based, and now we know that we will take all the backups.
Does Calendar based scheduling needs improvement: Yes (so the frequency one), like the precision of the starting point is still a little unstable within the 10 minutes (scheduler wakeup setting), however we don't really care if the backup will start 2 minutes before or after, with Calendar scheduling you know that your schedules will start, something that we can't say for the frequency ones.

Our environments: 4.5 FP3/FP5/FP6s.

Good Luck.

 

[rynardo]

I have a similar problem. Our policies state that every weekend, we execute full backups on all of our systems. All weekly backups are retained for 5 weeks. This isn't a problem because we use frequency scheduling, however, the problem starts when we attempt to run a schedule called "MONTHLY" on the last weekend of every month. This backup is the same full backup as the weekly, yet it has infinite retention. We decided to schedule this backup as calendar based. All was well until I attempted to get a MONTHLY backup for restoration of one of our systems. The backup was not retained because the policy spanned over friday night and saturday morning, and I had selected the last Friday of every month to be when the monthly backup runs. The client I listed was actually backed up on Saturdays, so the monthly backup never ran....
Has anyone had this issue? Is there any way to configure this correctly? I would appriciate any help...

 

[PGPhantom]

Calendar based scheduling does not work very well, period. The only way you can get it to work in your configuration ...
The backup window should be as short as possible - Veritas recommends 1/2 hour window. The calendar and frequency schedules must be part of the same policy. The start time must be exactly the same and the calendar must have a higher retension level than the frequency job.

i.e. Full backup starts Friday night on a Frequency schedule at 6:00 p.m. with a retension of 5 weeks. The calendar based backup must be set to Friday night at 6:00 p.m. as well.

 

[creakyjoe]

i second PGPhantom; my five cents - i've always used Frequency, wasn't in a hurry to try Calendar, but now i see that i haven't lost anything by staying with Frequency-based.
Frequency, if allowed to run amok, will not be reliable, but as long as you are very strict with it, it should be fine. I was having a few teething troubles upon moving to 4.5, found that 4.5 is less tolerant with backup window (ie it was quite lax before 4.5). My 4yr old backup windows were far too lax, ie 8hrs here, 10 hrs there, etc. Changed everything to 1hour, bingo, stuff runs as expected.

Rich