Speedware Sponsor Message

Hidden Value details commands and procedures in MPE that can improve your productivity with HP 3000 systems. Send your tips to john@burke-consulting.com.

Edited by John Burke

This morning I came in to find the backup job stalled. Abortjob was ineffective, as was abortio. I ended up rebooting the system. While coming up, I got the “defective sector” message with “FILE.GROUP.ACCOUNT has an extent with unreadable data.” The file is now locked and I need to use FSCHECK to unlock it. How can I determine which drive this extent is on? I have a good idea which one it is, but I’d like to be 100 percent sure before I replace and reload.

Stan Sieler replies:
FSCHECK’s DISPLAYEXTENTS command may help. Note that, if I recall correctly, it displays logical unit numbers, not exactly LDEVs.

We were going over our time change procedures and came up with questions about all the different time change methods and parameters and what they mean. For years we have automatically run a job on the time change Sunday at 1:59 AM that basically just changes the time zone. For the last couple of years we have also started running an NTP time synchronization job at 3:00 AM every morning. The TZ variable is set to PST8PDT. Now as I understand it, NTP is adjusting the UTC time. But does it also adjust the time zone? In other words, are we duplicating effort with these jobs?

John Clogg replies:
NTPDATE will not adjust the time zone. It will only accomplish the tiny adjustment to UTC time caused by the drift in your system’s hardware clock. There is no problem running both programs the same night, as long as your DST adjustment has completed when you run the NTP adjustment. Since the spring adjustment moves the clock forward, it will happen immediately. The autumn adjustment can take a couple of hours or more, so it calls for greater coordination.

I ran checkslt on the MPE/iX 7.5 SLT and it failed. It failed on a DDS-2 drive on two different systems but passed when a DDS-3 drive was used. The MPE/iX 7.5 SLT is on a 120-meter DDS-2 tape. HP, at present, is looking into this. Is this usual?

Michael Berkowitz replies:
What makes you think you don’t have two bad DDS-2 drives? When we had them, we went through them like water, replacing them every couple of months. They are bad news from the word go.

But how can I have two bad DDS-2 drives?

Gilles Schipper notes:
Not surprising at all. I once experienced the following situation. Our customer had a disk crash. Fortunately, it happened just after a full backup. HP replaced the faulty disk drive and we proceeded to perform a system reload from the just-completed backup that had been to a DDS-2 tape drive.

As soon as we mounted the tape (on exactly the same tape drive that created it), we received a console message indicating AVR error on LDEV 7. I knew right away we had a problem. HP returned to replace the tape drive with another DDS-2 drive. Still no joy. We recommended replacing the drive with a DDS-3 tape drive. As soon as this was done, the reload proceeded without further problems.

The bottom line is stay away from DDS-2 drives, as far away as possible. From this experience and others, I have concluded that the DDS-2 drive is, to put it mildly, flaky.

I’m setting Apache 1.3.4 up for on-line access to reports. I used the fancy indexing feature for the directory index, but when I display the index on a Web page, it’s truncating the links at about 22 characters. What can be done about this?

Mark Bixby replies:
You want to take a look at the NameWidth option of the IndexOptions directive: httpd.apache.org/docs/mod/mod_autoindex.html#indexoptions

Is a patch required to install disks greater than 9Gb on MPE/iX 6.0? I am trying to install a Cheetah 36XL, ST336705LW disk. I can format it, but it still shows as UNKNOWN when I do a DSTAT ALL. This disk is to replace the ST39204LW, which was a 9Gb version.

Scott Swartzell and Craig Lalley reply:
It sounds like you haven’t added the new disk to a volume set in volutil. If you can see the disk in dstat all, you probably don’t need a patch.

Stan Sieler adds:
The maximum size of a disk drive on MPE/iX varies depending upon which release (or patches) of MPE/iX you’re using. If I’m in doubt, I check the IODFAULT.PUB.SYS file, and search for “GB” to find what the largest supported disk might be. On our well-patched 6.0 system, I see: ‘3.50” 73 GB FC Disk Device’ which tells me that it had better support a 73 GB disk.

By the way, “support” is a slippery concept. For quite some time, MPE/iX hasn’t done a proper job of supporting larger disk drives. On 6.0 and later (perhaps earlier, too), MPE/iX would allow you to mount/use a larger disk drive than DISCUTIL (an important offline utility) would support.

The following does not appear to be a problem. But for my own edification I would like to know why this is so: We installed a used HASS Jamaica A3312A drive enclosure with two 9Gb FWD SCSI-2 drives. Both drive modules appear to be the same part number A5238A. I configured both drives in SYSGEN as ST39236LC as per instructions from HP support. However DSTAT ALL shows different IDs. Why is this?

John Burke replies:
DSTAT is actually reading the ID information off the drive. The difference between SYSGEN and DSTAT does not matter, though many people alter SYSGEN after the fact with the correct ID so it is in sync with reality. In configuring disk drives in SYSGEN, the only thing that really matters is that you get the correct driver. On your system there are only two, one for FW and one for SE. So choosing any FW drive would have worked.