SLC scsi disk problem

[Steve Maraglia]

I recently installed 3 Sun 4/20's (SLC's), each with a 150Mb external scsi
disk (Seagate Wren III model 94161). We've been getting the follow disk
errors on all three systems. On one system the errors occur 3-4 times a
day and the others 1-2 errors every couple days. They don't appear to be
fatal errors as the system continues to run fine, however, I'm very
curious to know if anyone else has experienced this problem and if anyone
can explain why this is happening?

/usr/adm/messages:

	esp0:	0.0 data transfer failure
		Stat=0x10<XZERO>, Intr=0x10<BUS>
		Last state='UNKNOWN', Last cmd='dma tran_info'
		DMA addr=0xff01a000, last=0xff018000;Dma CSR=0x80000000
		Mapped Dma Space:
			Base = 0xff018000 Count = 0x2000
		Transfer History:
			Base = 0xff018000 Count = 0x2000
	sd3:	SCSI transport failed: reason 'reset': retrying command


Disk label:	<CDC Wren III 94161-155 cyl 965 alt 2 hd 9 sec 35>

Steve Maraglia				   internet: srm at unify.com
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