Forum has lost connection to server

[#1]

I have had a small forum running for a couple of years using VBulletin. It was switched over to the ccgi address and worked fine. Some while ago I started to receive these e-mail error reports.
mysql_connect(): Can't connect to MySQL server on 'humbug' (4) /share/storage/04/tr/username/Forum_name/includes/class_core.php on line 274
(I have changed the actual user and forum names).
I have upgraded the VBulletin version but I still get the messages. Also the front page of the forum shows zero posts, although if you enter an individual forum all the posts are still there with posting dates and replies etc.
When I tested everything through the admin control panel it seemed to work OK but since then I have tried logging in as a normal user and it fails (and I get another server connectivity error report)
Any suggestions please as I can't remember how to access the MySQL database now (or what to do even if I could).
Many thanks.

[#2]

There have been a few issues with the SQL servers recently (getting close to their connection limit), although most reports are on Rumpus.
Does this happen all the time? i.e. does the time that you try to use this effect the success of connecting, or does it fail at non-peak times?

[#3]

The forum is used fairly infrequently but I have been back over the error reports and they seem to be at different times of the day, although there could be a slight bias towards peak times.
Is there any way that you know of where I can check out connectivity and get a trace on where the failure might be and why it is happening? I originally thought it was because the VBulletin software was not the latest version but that seems not to be the case. Thanks.

[#4]

http://community.plus.net/forum/index.php?topic=1335.0
I suggest you post in that thread rather than having 2 for the same problem.
There is nothing you can to to investigate this, its a problem with the MySQL servers which many are seeing.

[#5]

Thanks very much. I thought this was a specific problem with my DB and not a general problem. I will go to that thread.