SS2 data transfer overrun

[Brien L. Wheeler]

We are running a SPARCstation 2 with SunOS 4.1.1 Rev B.  Our SCSI configuration is this:

    esp0 - Emulex SCSI controller
        sd0 - Internal Maxtor 207MB - SCSI ID 3
        sd3 - External Sun 669MB    - SCSI ID 0
        st0 - External QIC-150      - SCSI ID 4
        sr0 - External CD-ROM       - SCSI ID 6
        ss0 - External Scanner      - SCSI ID 5

Occasionally the system will spit out error messages of a 'data transfer overrun' from the Maxtor 207MB:

esp0:	data transfer overrun
	State=DATA Last State=DATA_DONE
	Latched stat=0x10<XZERO> intr=0x10<BUS> fifo 0x60
	last msg out: <unknown msg 0xff>; last msg in: COMMAND COMPLETE
	DMA csr=0x94400010<INTEN>
	addr=ff072000 last=ff070000 last_count=2000
	Cmd dump for Target 3 Lun 0:
	cdb=[ 0xa 0x4 0xf9 0xe8 0x10 0x0 0x0 0x0 0x0 0x0 ]
	pkt_state 0xf<XFER,CMD,SEL,ARB> pkt_flags 0x0 pkt_statistics 0x2
	cmd_flags=0x27 cmd_timeout 35
	Mapped Dma Space:
		Base = 0xff070000 Count = 0x2000
	Transfer History:
		Base = 0xff070000 Count = 0x2000
sd0:    SCSI transport failed: reason 'data_ovr': retrying command
esp0:	Target 3 now Synchronous at 4.0 mb/s max transmit rate

Does anyone have any ideas on why this is happening?

-- 
     Brien L. Wheeler             |  I don't speak for MITRE, and they
     wheeler at bistromath.mitre.org |  don't speak for me.

"When I think back on all the crap I learned in high school..."