rescan-scsi-bus.sh: when there is a logical lun-0, testonline will spend 30s to retry-check it

[LiuXing108]

In function testonline, this shell uses sg_turs to check sgdevice, but lun-0 is not always a real device, sometimes a logical one. it depends on Vendor's implementation. So could we ensure there is a real sd-device before we check it by sg_turs?

[doug-gilbert]

Would something like 'if sg_inq $DEVICE | grep -q -i "PQual=0" ' work in this situation?

[LiuXing108]

it works：

testoneline() {
  ……
  sg_turs /dev/$SGDEV >/dev/null 2>&1
  RC=$?

  # Handle in progress of becoming ready and unit attention
  while [ $RC = 2 -o $RC = 6 ] && [ $ctr -le 30 ] ; do
    if [ $RC = 2 ] && [ "$RMB" != "1" ] && [ sg_inq /dev/$SGDEV | grep -q -i "PQual=0" ]; then
      echo -n "."
      let LN+=1
      sleep 1
    else
      sleep 0.02
    fi
    let ctr+=1
    sg_turs /dev/$SGDEV >/dev/null 2>&1
    RC=$?
……
}

[doug-gilbert]

sg3_utils revision 972 (subversion, as show in ChangeLog file) uploaded with the above change in it. Could you test it?

[LiuXing108]

I'm so sorry and embarrassed for https://github.com/doug-gilbert/sg3_utils/issues/24#issuecomment-1256902739. it has a code error - we should not add "[ ]".

[LiuXing108]

I'm so sorry and embarrassed for #24 (comment). it has a code error - we should not add "[ ]", I wrote it wrong. it should be like this: if [ $RC = 2 ] && [ "$RMB" != "1" ] && sg_inq /dev/$SGDEV | grep -q -i "PQual=0" ; then

and I tested this shell with "scsi-rescan -a -r "，there are two iscsi links on my server, as we expected, one link reduced 30 seconds。 after modificated： real 0m12.165s user 0m2.853s sys 0m2.450s before modificated: real 1m12.874s user 0m2.732s sys 0m2.353s

[doug-gilbert]

Subversion revision 973, now mirrored here, has the above fix. Perhaps you might recheck it has been done properly. Also that revision contains the patch discussed in the issue #22 .