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Geoff Molloy. Communications and Computing Branch Bureau of Meteorology Australia. Servers. · UNIX based Message Switching System · Currently ported to HP, IBM and Linux machines. Use HP and IBM internally Runs in 8 BOM offices (2 in Melbourne). Failover.
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Geoff Molloy Communications and Computing Branch Bureau of Meteorology Australia
Servers • · UNIX based Message Switching System • · Currently ported to HP, IBM and Linux machines. Use HP and IBM internally • Runs in 8 BOM offices (2 in Melbourne)
Failover • One issue is the mechanism for swapping to the backup machine if the primary is unavailable for an upgrade or has failed. On HP use a proprietary product called ServiceGuard and on IBM’s use HACMP. • Both work in the same manner: • heart-beats are exchanged between the servers via the LAN and via a direct link. • If the primary fails then the backup acquires the operational disks (which are always connected to both machines) • The backup also takes over the operational IP address. • The entire process takes 1-2 minutes. • This process ensures that other GTS centres only ever need to connect to one IP address.
Data Volumes • Currently receive about 450,000 messages and files per day (most domestic). • Send over 1 million messages and files. • Have about 120 input connections in MSS
Web Site: www.bom.gov.au • Is an increasingly important mechanism for getting data to the general public but also to specific customers. • 10Mbps internet link • Up to 8.5 million hits per day in severe weather situations. Radar loops very popular • Data is populated from Message Switching System • In the process of replacing our HP UNIX Web server with a cluster of Linux PCs.
Transmission mechanisms • Still issue about 10,000 faxes per day but is declining. • Use a polling fax system • Deliver voice files to a telephone weather service • Web • FTP via Internet (ftp.bom.gov.au) • E-mail output • Many links to private companies – airlines, private met companies • AFTN • Emergency services • Marine radio broadcast
Incoming domestic data • A lot of AWS use the telephone network. Some have leased lines and report every minute • Some co-operative observers have laptop PCs and they use the telephone network and TFTP to send messages • Some observations received via e-mail • Most ship reports received via satcom-C and the domestic X.25 network (Austpac) • Use ISCS (US International Satellite Communications System) • 64Kbps X.25 link to AFTN • Some data received via Internet – FTP to our external FTP Server (ftp.bom.gov.au) and retrieved by MSS (FTP get) • Radar – about 100 radars with data received by MSS every 10 minutes. Converted to image form and stored on Web server and sent to sleected customers.
International Links • Tokyo – 64Kbps leased line (WMO sockets + FTP) • Bracknell – 128/32K Frame Relay (WMO sockets + FTP) • Washington – sockets via Tokyo link. • Singapore – 128/8K Frame Relay (WMO sockets) • Jakarta – 128/8K Frame Relay (WMO sockets) • Malaysia – Internet (WMO sockets + FTP) • India – Internet (WMO sockets) • Fiji – 9600 leased line (WMO sockets) • Noumea – 9600 leased line (X.25) • Vanuatu – Internet (non-WMO sockets + FTP) • PNG – Internet (currently receive only) FTP • Solomon Islands – Internet but currently broken • Moscow – experimental Internet link (WMO FTP)