What is the meaning of the file names created by NetVault's LiteSpeed Fast Compression i.e., F0, D0, S0, etc?
Ok- here is how naming works. A FastCompression backup has the form:
<DatabaseName>.litespeed.<index>.bkp
The index is a 1 to 4 part naming index of the form f#[.d#][.s#][.m#]
f: Full backup id of backup taken by Fastcompression
Starts at 0 and incrementing
d: Differential id of backup taken by Fastcompression
Starts at 0 and incrementing for *each* full backup
Only exists if this is a differential
s: Stripe id of backup file
Only exists if this is a multi-stripe backp
m: Mirror id of backup
Only exists if this a mirrored backup (not a primary)
So:
F123.litespeed.f10.bkp: Eleventh full backup produced by FC (single-file, not mirrored)
And
F123.litespeed.f6.d1.s3.m2: Fourth stripe file of third mirror of second differential applicable to seventh full backup
There is one degenerate case where FastCompression has been instructed to create a backup and it produces a differential (non-escalation or prohibited from creating a full on that day)- BUT someone has gone and produced their own full backup… By nature of the way Sql Server works, this diff cannot be applicable to the last full backup taken by FC and thus it is not tied to a FC-Full-backup-id…
It is tied to the user full backup, in which case you get the odd syntax like: AdventureWorks.litespeed.f(AdventureWorks.bak 2013-05-01 10-07-06).d0.m0.bkp
Therefore, this is a FC differential backup (first mirror) of the AdventureWorks database that is applicable to a backup named AdventureWorks.bak taken on 5/1/2013 at 10:07:06 AM
If there is no FC full id- it uses” (<name> <datetime>)” as a placeholder so you can see what full backup it is applicable to…
This placeholder can be further shortened if there is not enough room due to file system path length restrictions.
