2006/01/24 - International Routing
It appears that Rhodes IP address block is not being correctly advertised to Telkom's international peers. As a result users at Rhodes will have difficulty connecting to some (but not all) international sites. This problem first started late yesterday afternoon and has persisted through the night.

The problem has been reported to Telkom.

For those who're interested in the details Rhodes has two separate IP address blocks, and These are advertised to the world by means of the border gateway protocol, and these advertisements allow networks in other parts of the world to route traffic to us. Since we're single homed, the BGP advertisements for Rhodes networks are handled by our upstream providers, in this case Telkom/SAIX.

It appears that BGP for is not being propogated accross Telkom's International links. We can tell this because if we attempt to connect to certain sites (eg. from a IP address it fails, whereas if we attempt to do it from a address it works. A traceroute from the block indicates that the last working router is A traceroute from shows that the next hop should be Telkom's peering router in the London Internet Exchange.

Once Telkom find and correct the problem that causing not to be advertised properly, it'll take some time to correct. This is because the BGP advertisement for our network block needs to propogate to each of Telkom's peering partners, and then in turn to each of their peering partners, etc.
It looks like this problem only affects sites that are transited through Equinix in London. International sites that transit via other providers (for example academic sites in Europe transited via Geant) work fine.

Our fault has now been escalated within Telkom.
During the course of today (Wednesday) we've seen this problem intermittently re-occur. We've still not had any real explanation from Telkom as to what's going on.