Arcserve 9 many problems

[GEMINI88]

We installed the Arcserve 9 +IBM LTO Tape Library +IBM NAS 200. Leaving the following problems unsolved two months after:

1. It's strange that it suddenly cannot backup files from our mail server, it mentioned:
Unable to connect to network drive. (DRIVE=\\CHLSRV01\ADMIN$, EC=TOO MANY SESS)
Information 2003/07/17 00:43:18 61 Note: Connect to \\CHLSRV01\ADMIN$ as .
But the backup job can access the server before, suddenly lost connection and the error persisted.

2. The network backup is extremely slow. The throughtput is 25mb/min, terrible. I followed the Arcserve support instruction to update the newest patch file but the situation does not improved. We even installrf the program to anther PC as backup server but the throughtput does not improve. It takes 20 hours to finish a 70GB backup job. Our LAN is under 100MB structure and the throughtput is up to 1GB if I copy file from the network.

Does anyone of you have the same problems?

Gemini

 

[mohamdr]

Hi
Is the 9.01 update is applied if not apply it in all machines contain Arcserve components.

Are you doing the backup througth client agent or througth the network.


regards the slowness issue what type of files are backing up are there you backing up databases like Exchange,sql...
if you are backing up exchange are backing up the brick level mailbox.


regards,
Mohamdr

 

[GEMINI88]

Hi Mohamdr,

We have already installed the 9.01 patch file. Before that, we can't even start up an scheduled backup job. The speed problem happens when we backup throught the network. No matter what type of files it is, the max. throughtput via network is 100m/min. and it drops to 15-25m/mins while backuping small word and excel files.

We do installed the client agent but it cannot not be applied on my snapserver as the 40GB snapserver runs on its proprietary os. We are using Lotus Notes and therefore no exchange or sql running.

I search from the web and lots of people complaint on similar problems on Arcserve. Anyway, I am planning to build an isolated environment from my LAN to identify whether the problems caused by the network or it is simply an Arcserve problem. Will share my experience once got the conclusion.

Gemini

 

[kvacker]

Our backup was extremely slow too. We found the server was set at full and 100 but the switch was set at half and 10. Soon as we made the change we were flying. Our Acrserver is on Windows 2000 server backing up novell servers using the agents. We do have the novell client installed on the windows 2000 server running Acrserve. We also backup ms servers without agents and get very good through put. With the agents for Novell you have to use the full login name like .cn=user.o=organization.

Kevin

 

[ACiDelic]

1. "TOO MANY SESS" means that ARCserve cannot map the ADMIN$ share because there are already too many sessions connected to that share. There is a session limit assigned to each share. You should check (using Computer Management) to see who has made all those connections to ADMIN$ and if necessary increase the number of concurent sessions allowed for this share.

2. The throughput of a job over a network can be affected by many things:

Anti-virus is the worst culprit. If you have anti-virus running on the machine, try turning it off and see what kind of throughput you get.

Activity on the drive can slow things down. Try running the backup when there is little or no activity on that machine.

Network traffic. Heavy network traffic can an will slow down your backups.

NIC configuration can cause the connection to use a slower speed. I can't remember where, but I'm referring to the NIC settings such as Full-duplex/half-duplex, 10 baset, 100 baset, etc. If you are using something other than Auto this may cause you a slowdown.

 

[GEMINI88]

Thanks all for comments.

We tried to reinstall the Arcserve 9 and some of the error disappered. (We installed the arcserve at the IBM NAS 200 server) Here are throughput to share:

IBM NAS 200 (Local in Win2K) 950MB/Min
IBM X232 (via LAN in NT4) 350MB/Min
IBM Server 330 (Via LAN in NT4) 60MB/Min
Quantam Snap Server (Via LAN) 25MB/Mins

I have checked the LAN performance and it is in 100 base with good performance. We set the backup job at night when no one are using the network. Is the figure normal or still have something to boost it up?

 

[NorbertNetzwerk]

Gemini88,

have you checked the blocksize that AS is using for the LTO drive? It used to default to 16 KB which is way too small for DLT or LTO drives.
Here is a support doc from CA on this issue, relating to AS 6.6x. Might still be valid on newer versions:

"All DLT products are optimized for use with large block sizes. Block size specifies the size of the chunks of data written onto tape.

ISSUE: Block sizes of less than 64 KB for DLT1/DLT VS80 and 32 KB for all other DAT and DLT drives can drastically increase the backup/restore time and severely affect the performance of the drive.

SOLUTION: Most backup applications allow viewing and adjusting the block size used for a particular device. See below for advice on how to achieve this for CA ARCserve, Veritas Backup Exec and Tapeware.

CA ARCserve (for Windows NT)

See CA Technical Support Article "NT-AS6: Title: Changing the block size for a DLT drive":

http://support.cai.com/techbases/asnt/NASNT123.html

ARCserve for Windows NT version 6.x defaults to a write-block size of 16k for DLT drives. In order to increase performance, make the following changes in the Windows NT registry, using REGEDT32.EXE:

1.HKEY_LOCAL_MACHINE \SOFTWARE \Cheyenne \ARCserve\CurrentVersion\TapeEngine\Device#
(The device number corresponds to the tape drive that will require a change in block size, this is located in the Device Manager)
2.Click Edit, then select ADD VALUE:
ValueName=DefaultBlockFactor
Data type = Reg_DWORD
Data: 6, Hex

In addition to 6, the following values can also be selected:

0 = 512 (default) 1 = 1,024 (1 KB) 2 = 2,048 (2 KB) 3 =
4,096 (4 KB) 4 = 8,192 (8 KB) 5 = 16,384 (16 KB 6 = 32,768 (32 KB) 7 = 65,536 (64 KB)

After making the change, stop and start the ARCserve Tape
Engine, then try another backup.
"