Re: Windows Server 2003 Tape Backup Compression Problem
- From: "Pegasus \(MVP\)" <I.can@xxxxxxx>
- Date: Sat, 10 Jun 2006 21:27:17 +1000
"Donald A. Martin, Jr." <Martind@xxxxxxxxxxxxxxx> wrote in message
news:1149889182.855740.219570@xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
Hello,
We are having trouble with the tape backup on two of our area servers.
Both servers are running Windows Server 2003 Standard Edition with
Service Pack 1 applied. Both are Dell PowerEdge 2600 servers with
Seagate Digital Data Storage Type 4 drives. These drives have a
capacity of 20GB native and 40GB compressed, as do the tapes. All
firmware is up to date. We are using the native Windows backup
software.
The problem we are running into is that after the backup passes the
20GB mark the backups have started failing. Compression appears to be
working as the backup will go above 20GB but will fail well below 40GB.
It doesn't appear to be hardware related as we have replaced the
tape drives but are still experiencing the same problem. We have 17
other servers that are configured the same way and all of them
successfully backup between 22GB and 38GB nightly. The Servers have
been cold-booted. Both servers used to backup well over 30GB regularly
but have just started having trouble the last couple of weeks.
When we ran manual backups I noticed that the failure occurs when the
amount of data backed up exceeds the "Estimated" bytes. For
example, while Windows estimates it will be backing up 26,986,495,086
bytes the backup reaches 27,395,642,141 bytes then fails because the
tape is out of space. It appears that there is something within the
backup software that is contributing to this problem but we have been
unable to find anything on Microsoft's website or in the news groups.
Any help with this problem will be greatly appreciated.
Thank you,
Donald A. Martin, Jr.
Seagate have a habit of quoting tape capacity in normal and
compressed mode but they often fail to make it clear whether
the specific drive provides inbuilt data compression. One of
mine did not and it took me a long time to work out that I was
supposed to do my own compression.
On average you will get around 50% compression. However,
if you back up many large files that are already compressed
(e.g. .zip, .jpg or .mp3 files) then your compression rate will
be much less, for obvious reasons: You cannot compress
compressed files!
.
- References:
- Windows Server 2003 Tape Backup Compression Problem
- From: Donald A. Martin, Jr.
- Windows Server 2003 Tape Backup Compression Problem
- Prev by Date: Re: backup up two W2003 servers: Windows Backup or Third Party
- Next by Date: Re: Need Help RE: NTFS
- Previous by thread: Windows Server 2003 Tape Backup Compression Problem
- Next by thread: backup up two W2003 servers: Windows Backup or Third Party
- Index(es):
Relevant Pages
|
