2006/03/04 - Network Outage, Upper Half Of Campus
On Saturday 4th March we'll be moving the fibre optic terminations for the upper part of campus from the Catering building to the new African Media Matrix building. This is a major undertaking that is only expected to be completed during the course of Sunday afternoon.

During this time users who connect via the existing Catering switching centre will experience several intermittent disruptions in network connectivity. These interuptions will be of varying duration and may last up to a few hours.

Affected areas include all residences in Kimberley hall, all residences in Nelson Mandela hall, all residences in Hobson hall, all residences in Oriel hall, the aforementioned dining halls, all private houses in Gilbert Street, the Gavin Relly Postgraduate Village, New House, Adamson House, Livingstone House, Jan Smuts dining hall, Transport/Maintenence Stores, Furniture and Equipment Stores, Campus Protection Unit, the Psychology Clinic, Fine Art (Sculpture), Catering, and the African Media Matrix building. Telephony in the African Media Matrix building will also be affected.

As there will be no warning as to when specific areas will be disconnected, users are strongly encouraged to plan around this outage working on the assumption that networking will be unavailable in the above areas for the entire weekend.

Updates and further details will be posted below.
For those of you who are interested, the technical details of this outage follow:

For a long time the Catering switching centre has been the major supplier of connectivity to most of the upper campus. As it was retrofitted into the building, it's never been an ideal location (small, difficult access, no proper cable routes, etc) so with the advent of the African Media Matrix we've taken the opportunity to improve things. This regional switching centre will go from being a major layer two centre to being the only other major layer three switching centre on campus (apart from Struben building that is).

During the course of the weekend a lot of different work is going to be done. Those fibre optic cables that currently run past the AMM building (Nelson Mandela, etc) will be pulled back in their sleeves and re-terminated in the AMM building. Those fibre optic cables that enter catering from the Furniture stores side (Jan Smuts, etc) will be spliced onto a new cable to extend them and then re-terminated in the AMM building. In all about fifteen separate cables, each containing a varying number of fibre optic pairs, will be moved and re-terminated. This is a time-consuming process, but we'll try and minimise the downtime experienced by individual areas by carefully selecting the order in which splices and terminations happen to ensure that dependencies are met quickly.

In addition, the catering switch itself will be replaced with a new Nortel ERS 8600 that was recently installed in the AMM building. This switch offers significantly increased capacity as well as layer three routing, and forms part of our redundancy plan for campus.

As a result of the switch upgrade we'll be in a position to upgrade several of the fibre optic links to other sub-regional centres. Where possible these links will be upgraded to 1Gps by replacing the existing 100Mbps media converters with GBICs of various descriptions. This will happen simultaneously with the fibre splices.

If all goes well with the above, we'll take the opportunity on Sunday to configure an Inter-Switch Trunk between the ERS 8600 in Struben building and the ERS 8600 in AMM. This will allow us to manage these two switches as a single unit and effectively give us a distributed backbone on campus.
As of about 7PM this evening, the fibre splices and terminations are complete.

Unfortunately connectivity has not been restored to all affected areas. Currently the following areas have no access: all residences in Oriel Hall, all residences in Hobson hall, the aforementioned dining halls, Nelson Mandela dining hall, Gavin Relly Postgraduate Village, and Furniture & Equipment stores.

By and large the reason that these areas have no connectivity is that we've been unable to gain access to the relevent areas. For instance, in the case of Oriel & Hobson halls, the dining halls closed at 7PM and effectively precluded us from doing any further work on those areas.

Where possible we'll try and restore access to these areas during the course of tomorrow. It's likely, however, that connectivity may only be restored to these areas on Monday.

There's likely to be one further outage to all areas during the course of tomorrow as we configure an inter-switch trunk on the core switch in AMM.