2012/08/08 - Network problem affecting Main Campus sector
Since this morning, we have been experiencing a recurrence of the problem described in this post:

We have attempted to diagnose the problem and are in the process of reporting the problem to the router vendor.
A representative from the vendor's technical assistance centre has attempted to diagnose the problem, but was unable to do so. He is now in the process of escalating the problem to the advanced technical assistance centre, and we will hopefully hear from them during the course of this evening.

Unfortunately, in order for the vendor's staff to be able to diagnose the problem, we need to keep the routers in their current, not-fully-functional state. This means that staff and students using PCs within the main campus sector* will experience problems accessing network services. We've received reports that some PCs are unable to access any network services (particularly PCs that've been rebooted recently), but that they can tend to recover after some time.

* The main campus sector is bounded by Somerset St, Prince Alfred St and Lucas Avenue, as far as the Biological Sciences Building, the Library and the Psychology Building, as well as the Law Clinic, Mandalay-off-High and 36 Somerset St.
After some confusion about time zones, we've now got the vendor's advanced technical advice centre looking at the problem. They are performing diagnostics on the router as I write this.

We'll reboot the router as soon as the ATAC has finished gathering information from it, or before start of business tomorrow (Friday), whichever comes first.
The ATAC have completed their diagnostics. While they have not been able to identify the root cause of the problem, they will be analysing the information they've gathered and will advise on a course of action.

The routers have been rebooted, and network service should be restored to normal now.