It's one of *those* Fridays.

It seems we've been having problems inserting data into the main ResNet database.  I'm not sure how long it's been a problem, but it looks like it may have been a couple of days now.  I've cleared the problem now - if you were having problems registering, please try again.

If your connection is fully working, there is no need to take any action.

Most people on ResNet won't have noticed, but one of our servers dropped off the network at about 7pm last night due to a problem with one of it's network interfaces. Things that will have been affected include:

• Registration System
  The server that fell over provides the DNS for the registration network. It's set up to redirect all requests for web pages to our registration system. Your connection will have fallen over to the secondary DNS, but the secondary isn't set up in the same way - so your web page requests won't have been diverted.If you typed in the url for the registration system directly, you will have been able to register OK.
• Manage My Resnet
  Bandwidth reports for last night won't have been updated.
• Network Status Monitoring
  The traffic lights on the ResNet home page which monitor the status of the network won't have been updated.

Normal service was resumed at 9am this morning which was the first available opportunity for me to have physical access to the server.

One of the central University database servers is being restarted at 8m on Friday 27th July 2007. This is expected to take about half an hour.

This maintenance will cause problems with the following parts of ResNet;

• Registration system
  New users will not be able to register for the duration of the maintenance period.
• Manage My ResNet
  Some parts of Manage My ResNet will be unavailable for the duration of the maintenance period.

Existing ResNet connections will remain active, and most users won't even notice. For more details about other University services which will be affected by this maintenance - see http://www.bris.ac.uk/is/news/2007/stellar27jul.html

I've just noticed that one of our servers fell over at 7am this morning. I'm not in Bristol so I can't go in and switch it back on, and unless one of the other permanent staff happens to be in the area - the following services will be unavailable until Monday morning.

• In room registration process. New users will not be able to register their connections.
• Manage My ResNet - You won't be able to get to this at all, so you won't be able to see your bandwidth usage (although we're still counting it!)
• ResNet software archive (http://download.resnet.bris.ac.uk/pub) will be unavailable
• The short version of the URL for the ResNet website (http://www.resnet.bristol.ac.uk) won't work, although the long form will (http://www.bris.ac.uk/is/computing/advice/homeusers/resnet/)
• There may be a handful of other services that don't work as expected, which I've forgotten. But it's Saturday morning and I haven't had breakfast yet.

All existing ResNet connections should continue to function as normal.

Update: I have just kicked the box back into life - it is back up and all services are running as expected - sorry for any inconvenience caused. Mark.

We seem to be having some problems with Manage my ResNet - which may mean that people are unable to use it to check their bandwidth usage and/or sign up for the IPTV trial. I am investigating.

Update: The problem seems to be with our database link between the ResNet database and the main university database. Independently the two databases are working on their own, they are just not talking to each other. I'm just off downstairs to make the database admin team aware of the problem.

Update: Just as I hit save on that last update, the problem seems to have fixed itself. There should be no problems logging in to Manage my ResNet as of about 12:13pm today.

Update - 10:02am
It's all fixed.  Sorry for any inconvenience caused.

It seems that we're having database problems at the moment, We can't look up anyones details in the central university database.  From digging in the logs, it looks like the problem started at about 01:15 this morning. The following systems don't work:

• Manage My ResNet
• ResNet in-room registration system

If you try to log in to either of these systems, you're likely to get the following error message "Sorry, we couldn't find anyone in the University database with that username"

We're working with the database administration team to try and work out what the problem is and to fix it asap.

The database server we use is due to be taken down for some routine maintenance on the 2nd January 2007. The vast majority of ResNet users won’t notice, although the following services will be unavailable during the maintenance.

The Registration System - people trying to set up ResNet for the first time, or with a new computer will not be able to register.

Manage My ResNet - you won’t be able to check your bandwidth usage, your account details, or move rooms.

ResNet status monitoring - you won’t be able to see if there are network problems on ResNet

That’s pretty much it.

Other systems around the University may be affected, please see http://www.bris.ac.uk/is/news/2006/sys2jan.html for more details.

For a period on 18th December between 8am to 10am the following ResNet services will be unavailable

• ResNet online registrations
• Manage My ResNet
• ResNet automatic status monitoring

This is due to an urgent need to move power supplies in several racks in the machine room - the server our database is hosted on is one of those systems affected.
Actual ResNet connections will be unaffected - you can keep on using ResNet.

The ResNet database has been switched off. This is so that the machine that it runs on can be attached to a new super quick network filesystem. Sorry we didn't tell you earlier.

Luckily, this work will not affect most ResNet connections:

• If you are a current ResNet user, the Manage my ResNet utility and the automatic status monitoring on our homepage will be unavailable for most of the day. Otherwise, your internet connection should be unaffected.
• We will not be able to move your connection if you are moving room/hall until the database is back on.
• If you are a new ResNet user and need to pay us, we will be able to take your money, but we will not be able to switch on your account until after the database has been reactivated. Usually this would be instant.

Update: this was restored by about 11.45am this morning.

On Sunday 12th November @ 22:30 one of the 4 proxy servers that ResNet users use to surf web sites crashed because its log file became too full. The initial question should be "how did we let the log file get so big?". Well, the log file is able to get to 2GB in size before it fails, which under normal circumstances is more than enough, especially as we rotate the logs daily. However, one user's machine was making about 100 requests per second (over 8 million per day) to this server which caused it to crash. The user in question has been disconnected from ResNet until we can find out what software was causing the problem.

Most of you probably did not even notice the server fail as all its traffic was automatically moved onto one of the other three proxy servers with the failed server back up by 9am on Monday. One good thing to come out of this is that we have now changed the way we load balance our proxy servers in the event of an error. Instead of one proxy taking the load of the failed one, doubling its load, the traffic is spread evenly between all remaining servers so only increasing load to each by one third.

Another result of the 8 million connection attempts in one day was that the log analysis server crashed a day later because it ran out of disk space due to the larger logs that were copied to it It never rains but it pours!! This is being fixed by adding a larger disk. Well the original disk was only 18GB, it will soon be a whopping 36GB!