November 2010 Archives

Things are back to normal; reboot your workstation (alt-ctrl-F1 then alt-ctrl-del) if things are weird for you.

We are having a problem with our server infrastructure today: late this morning this resulted in workstations freezing for 30 seconds or so two or three times; over lunch, the server had to be restarted; and early this afternoon some workstations are unable to access home directories.

We are working on the problem.

Mail delivery, web sites and Windows file sharing are not affected.

Firefox, Thunderbird and Adobe Reader have been upgraded on the ms workstations. Things may be a little weird until you restart these applications.

We've had complaints of pine (and other command-line applications) being painfully slow in the past few weeks. It appears that this is almost always the result of logging in from off campus via VPN. Our own testing has shown that the slowness disappears when one shuts off VPN and connects directly to ms.mcmaster.ca.

We don't know yet whether this is a result of a change in the UTS VPN service or load or whether it might be due to an interaction between the new server and the UTS service ... though the former seems far more likely than the latter.

UTS is aware of the problem.

There were two power failures last Friday morning: the first at ca. 1:15 am was brief and only took out systems which were not on battery backup. The second one, at ca. 8:50 am, lasted about ten minutes and took out most systems on battery backup as well.

My thanks to the sysadmins who helped pick up the pieces in Math & Stats while I was enjoying my holiday in blissful ignorance of the problems here on campus.

HP is sending us a replacement for the HH-303 HP LaserJet 4345 printer/scanner, but it will not arrive until the week of November 29th.

If you want to avoid jams and smudges in the meanwhile, please use the HH-403 printer. If the HH-303 printer jams on you, here's how to deal with it ...

I've reactivated the HH-303 printer for now - partly, I confess, in order to generate more error data for HP. But during some testing this afternoon fewer than 20% of the pages jammed and while that's dreadfully frustrating, it's not completely maddeningly useless.

I hope to have this resolved soon.

We've experience more than our share of computer woes this week: in the department, across campus, and beyond. Most things have settled down as of late Thursday evening.

In Math & Stats

The HH-303 printer has gone from bad to worse: I disabled printing on Tuesday while I get HP to deal with this properly. Scanning still works just fine. The HH-403 printer is the main alternative.

Campus-wide and Beyond

Tuesday saw problems with some UTS systems such as univmail, resulting (as I understand it) from the strain of catching up after the Internet outage.

All systems are back up as of 9 p.m. using borrowed file-storage space. We're still shuffling files around and so the server and workstations will feel a little bit slow for a few hours.

We have no reason to believe that any data was lost and post-poned mail deliveries should be finished come Friday morning.

Note that while email and workstations were down much of the afternoon and evening, the web sites have been up since 4:00 p.m. (and up and down earlier in the day).

We will be transitioning to a permanent storage space of our own next week; brief downtime periods will be announced in advance.

We'll should have everything running again some time later this evening using the borrowed file-server space. There might be some brief un-announced downtime on late this evening or Friday. There will be plenty of notice before we shift back to our own upgraded storage in a week or so.

It might be necessary to reboot your workstation: just press Alt-Ctrl-F1 and then Alt-Ctrl-Del.

Note that web sites are already up - we were able to shift those to another file server much earlier.

The flakey (though new) storage server continues to be flakey and will not stay up long enough for us to get the file updates to the fail-over storage. We have disabled logins and email for the next hour or so.

Web sites remain up using a different file server - though changes made this morning are not reflected as we are using last night's backups.

While our new server is stable, we are having repeated problems with a borrowed storage server: it crashed yesterday afternoon and again this morning, taking email, web sites and the workstations down with it.

As we speak, we are getting a fail-over system ready ... two, actually. Workstation and mail performance will suffer while we are copying data from the current system.

There will be brief periods of downtime without advance warning so that we can take the unreliable storage system out of play as soon as possible.

Note that you can subscribe to Computing News blog entries to keep abreast of service announcements - see the SUBSCRIBE VIA EMAIL in the right-hand column.

I've shut down the queues for the HH-303 printer because it is jamming too often to be useful. Please use the HH-403 printer for now.

I'm now working with HP Level 2 support (that's meant to be good) and hope (pray?) that we'll have the printer fixed or replaced soon.

The scanner can still be used.

Some email messages delivered following the end of yesterday's network interruption will have confusing timestamps: the messages are stamped with the date and time of their arrival on our servers, not the date and time at which they were sent. And even though our network connection has been up since 7:30 a.m., some messages will arrive up to several hours later as the upstream servers only attempt delivery periodically.

McMaster's internet connection was down from mid-Monday afternoon until 7:30 this morning. Apparently a fibre-optic cable belonging to out upstream provider was cut.

Email sent to your @math.mcmaster.ca or @mcmaster.ca addresses during the downtime will either have made it through when the network came up or will have been bounced back to the sender with a warning message.

That thing I said yesterday, after we had much of the guts of the printer replaced? About it being OK? I was too optimistic.

The printer is jamming less frequently, but still jamming with frustrating frequency. Our problem has been escalated to a higher support level by HP, but we can expect to be dealing with this situation until early next week. Nevertheless, I'm optimistic that the final solution is in sight :)

That said, the jams may be dealt with easily and predictably ...

1. remove paper

1. it's usually behind the the output unit on the left-hand side, even when the LCD says that it's a Tray 2 jam


2. open and close top of the printer

1. not the scanner bed
2. the latch is on the right-hand side as shown at right

I'm working on the streaking - though I might not be able to do anything about it myself. If you need pristine pages, please use the HH-403 printer.

The printer/scanner outside of HH-303 has been giving us grief for two months, despite have parts replaced three times - but I think that it's finally OK! A new technician looked at it last week, identified worn parts and this morning he replaced them.

Note that the printer is streaking right now; that should fade away after a few dozen pages.

Let me know if you encounter any problem with jamming.