4. Central Servers

4.1. Sable

The number of users on Sable dropped from 15,000 to 11,000 in September 1999 after the new undergraduates were pre-registered with Herald accounts for email [figures 38 & 39]. During the year, Sable has had a few outages: some for hardware reasons (replacing a tape deck and disk) and some for operating system kernel bugs (whose symptoms are usually that an ever increasing number of unkillable processes make a scheduled reboot necessary). A bug in the Compaq daemon program that handles incoming connections for telnet, rlogin, IMAP and POP means that it occasionally dies, leaving the secure login method of ssh as the only access method until the errant daemon program is restarted. The number of users is now low enough that there are no longer any performance problems [figure 40].

Consideration is now being given to the consolidation of the Sable workload onto Ermine, possibly in summer 2001. Thereafter, it may be worth moving the whole workload onto a PC-based system, which would be much more economical to operate. However, that will depend on the level of demand for an ongoing Unix service.

4.2. Ermine

The number of users on Ermine has decreased from 8,000 to 7,000 as more email-only users migrate to Herald. During the year, Ermine has had a few outages: some for hardware reasons (replacing a faulty memory card and a firmware upgrade) and the others for similar reasons to Sable's outages.

For both Sable and Ermine, the POP protocol email service has given endless trouble, so it is planned to discontinue that service, with users being urged to either convert to IMAP protocol or move to Herald as the POP server (the service on that computer is more robust). In general, the POP protocol is deprecated in favour of IMAP, which supports much greater mobility.

4.3. Special Printing Services

OUCS operates a number of special printing devices, which are typically more expensive than any one department or unit can afford, and only by aggregating demand across the University are they cost-effective. They include:
  • a high-quality colour print and copy unit (Canon CLC 950);
  • a typesetter producing camera-ready copy (Monotype Prism PS Plus);
  • a high-performance Colour Postscript Printer/Plotter (HP DesignJet 755CM A0/A1).

Usage on these devices has been steadily increasing, and Operations staff make a point of providing professional quality output.

4.4. Computer Room Operations

The computer room is staffed from 08:00 until 22:00 each weekday. Operations staff are responsible for all operational duties associated with the large number of computers and network equipment housed there. This includes the central Unix computers, the HFS and its robot tape library, all the network servers, the servers for the OUCS departmental network (including teaching and public area computers) and servers associated with the NSMS service. In addition, OUCS houses (a limited form of Facilities Management) various major computers belonging to other University departments and units; these include the large supercomputers housed on behalf of Oscar and the Materials Department, the main OLIS Library and other library systems, servers for Central Administration and the Bioinformatics system.

All this equipment is protected by a large UPS system, and multiple airconditioning systems (for resilience), and of course with various physical security measures [figure 43].

In addition to standard operational services, the evening operations staff also provide a degree of help to users in the Work Area. Evening staff consist of one permanent employee plus a collection of casual staff, mostly drawn from the ranks of postgraduates.

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