[MAPREDUCE-473] Hook InetAddress.getLocalHost().getHostName() to support cluster simulatation.

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved

Environment

all

• Assignee: Owen O'Malley
• Reporter: alan wootton
• Created: 05/May/06 05:39
• Updated: 20/Jun/09 07:57

Description

I have been running a simulation for weeks now (and also a 30 machine crawl). To make it work I need to sometimes
let DataNodes, and TaskTrackers think they have a different machine-name than the one in InetAddress.getLocalHost()

The patch is:

1) replace InetAddress.getLocalHost().getHostName() with xxxx
1.a)xxxx could be "conf.get("inetaddress.localhost.name",InetAddress.getLocalHost().getHostName())"
1.b)or, xxxx could be a static call, I chose the latter: "InetAddressWrapper.getLocalHostName(conf)"
2) InetAddressWrapper.getLocalHostName(conf) checks the config for a hostname, and then calls InetAddress.getLocalHost().getHostName()

There's 3 places where it happens:
DataNode
DFSClient
TaskTracker

I did not patch the two tests that call InetAddress because they are not really using hostname.