Re: Premature overwriting of level 0

[Paul Bijnens]

Vytas Janusauskas wrote:

Setup:
20 tapes (VXA-2 v-23) Native capacity 67GB.
1 dump cycle.
Amanda version 2.4.2p2
Holding disk 105GB
All DLE are Samba shares for Win95/98/NT6/Win2000.
Problem:
I am now 7 tapes into the second rotation and the level 0 backups are 
being overwritten.  It seems to be due to the large size of 
incrementals being archived on a daily basis.  There are numerous days 
where Amanda only does incremental (level 1) and even so Amanda is not 
able to fit them all onto the daily tape.


So you have a dumpcycle of 28 days (assuming you run only on
weekdays) and a runspersycle of 20.
One of the disadvantages of a large dumpcycle is that the
incrementals take up so much space; and having only level 1
incrementals of smbclient makes this even worse, as you can see.
I can't garuantee it works much better, but giving the large
holdingdisk you have, I would give this setup a try:
tapecycle 20 tapes
dumpcycle 14 days
runspercycle 10
runtapes 2
inparallel 10
dumporder "TT"  # or S's
taperalgo largestfit
This will dump up to 67*2=134 Gbytes each day.
Once tape is filled during the backup, leaving up to 67 Gbyte in your
holdingdisk to be flushed on the next tape each morning.
The dumporder and taperalgo parameter help to fill the first tape
up to the last byte.
If you have any money left, I would add a second set of 20 tapes too.

Paul

Re: Premature overwriting of level 0

[Vytas Janusauskas]

Hi,

Setup:
20 tapes (VXA-2 v-23) Native capacity 67GB.
1 dump cycle.
Amanda version 2.4.2p2
Holding disk 105GB
All DLE are Samba shares for Win95/98/NT6/Win2000.
Problem:
I am now 7 tapes into the second rotation and the level 0 backups are being 
overwritten.  It seems to be due to the large size of incrementals being 
archived on a daily basis.  There are numerous days where Amanda only does 
incremental (level 1) and even so Amanda is not able to fit them all onto 
the daily tape.  Paul (see below) suggested as one of the options is  to 
patch Amanda to allow a higher level (2,3,4...) backups to be done with 
Samba shares, thereby reducing the size of daily incrementals.  I know that 
this would result in greater numbers of tape that would have to be accessed 
to restore the data but I am willing to live with that issue.

Solutions?
From Paul's response I may have wrongly assumed that all that would be 
required to "fake" level 2, 3 etc... backups would be to toggle the windows 
archive bit when Amanda is doing incremental archives.  Unfortunately, I am 
not a programmer. Though I did searched through the source code I could not 
find where to add the switch archive bit code.   If I am not completely out 
to lunch, I would appreciate any pointers required to implement.  If I am 
bouncing off the walls any other suggestions to solving my problem are 
appreciated as long as it does not involve additional hardware.

Thanks all!

Vytas

At 11:07 AM 3/24/03 +0100, Vytas Janusauskas wrote:
What must I do to ensure that all my level 0 are not overwritten before 
they are archived a second time? I have days where lots of new files get 
created. Can some explain why none of my backups are ever level 2 or higher?

At 11:07 AM 3/24/03 +0100, Paul Bijnens wrote:

When using smbclient to backup the builtin tar command uses the "archive 
bit" of the FAT/NTFS file system to determine "incremental" backup.
The bit contains only a enough state to emulate a level 1 incremental backup:
A full backup runs:
smbclient ... -Tqca -
-a means reset the archive bit
An incremental backup runs:
smbclient ... -Tqcg -
-g means only files with archive bit set, i.e. everything
changed since last full backup.
It's a limitation of PC filesystems and smbclient. There once existed
an idea to modify the amanda sources to reset the archive bit on
incremental runs too, and let amanda do the bookkeeping on the dumplevels 
but I've never seen patches for this...

Vytas Janusauskas
Dendron Resource Surveys Inc.
880 Lady Ellen Place,  Suite 206
Ottawa, Ontario, Canada
K1Z 5L9
Voice: (613) 725-2971
Fax: (613) 725-1716

Re: Premature overwriting of level 0.

[Vytas Janusauskas]

Hi Amanda Users,

I have 20 tape for daily archiving.  I have successfully done one pass 
through the tapes with Amanda.   I am now back to tape 4 up to this point 
all Level 0 archives to be overwritten have been redone.  I am coming up to 
tape 5 tomorrow and from looking at the amoverview table I see one to the 
DLE level 0 will be overwritten.  Today's amdump for the DLE in question 
states:

 vxa2://pent20/pent20-c   1 [dumps way too big, must skip 
incremental dumps]

Yes all the DLE I am archiving are Windows disks.  The above message has 
been appearing in all my Amanda reports for various DLEs.  What must I do 
to ensure that all my level 0 are not overwritten before they are archived 
a second time?  I have days where lots of new files get created.  Can some 
explain why none of my backups are ever level 2 or higher?

Amanda version 2.4.2p2.

Thanks

Vytas









Vytas Janusauskas
Dendron Resource Surveys Inc.
880 Lady Ellen Place,  Suite 206
Ottawa, Ontario, Canada
K1Z 5L9
Voice: (613) 725-2971
Fax: (613) 725-1716