sotn (2/8/2013)
thanks for the all the replies,if no activity is performed for 12 hours (overnight) then does not seem make sense to perform 24 tlog backups with no real activity. so that is why we do not have tlog backups 24/7 but of course I can easily change the plan to do this.
If that fits your recovery plan then so be it, can you be absolutely sure that no one has made a critical update that may be lost?
sotn (2/8/2013)
Therefore then, if we do tlog backups every 30 minutes 24/7 and a full backup nightly, and restore a full backup then leaving the destination DB in standby, we can 'report' against it with only 30 minutes latency, or do we need to kill connections to the destination in order to apply the tlog/see the new data.
Depends on how often the copy and\or restore jobs run. For the copied log backups to be restored the users will need to be disconnected. If the restores happen every 15 or 30 minutes then users will get pretty upset 😉
It's not unreasonable for the LS backup job to run every 15 or 30 minutes and have the copy and restore jobs run only twice a day for example, although in reality the copy job frequency should ideally match the backup to avoid copying lots of files in one go. once they're on the secondary the restore job could run twice a day maybe
sotn (2/8/2013)
One more question, if it takes more than 1 day to copy a backup from source to destination this is not a problem as Log Shipping will bring the destination up to date (i.e. apply over 50 tlog backups) providing all tlog backup files are still available on the source.
In an ideal world the full backup is used once to initialise the LS plan, after that the restored t-log backups keep the primary and secondary in sync.
That is until someone or something comes along to wreck your LS scenario. Even then, depending on the timeframe and backup regime in place, it is usually possible to fix a broken LS scenario without having to completely re initialise.
-----------------------------------------------------------------------------------------------------------
"Ya can't make an omelette without breaking just a few eggs" 😉