Archives for the Month of April 2006 on Chet Ramey's blog
Top talkers, listeners reports available
There is a new entry on the Network Engineering statistics web page listing the top 50 consumers of Internet bandwidth in both incoming and outgoing directions.
http://tisstats.case.edu/net/netstats/netflowstats/
There is an explanation of the numbers and a pair of links, one each to the top 50 consumers of incoming and outgoing bandwidth, respectively.
There is, unfortunately, no archive on the web page yet. Each day's table simply overwrites the previous day's report.
The job to produce the tables takes over 8 hours to run, so the previous day's stats don't appear until late in the afternoon. Nothing to be done about that yet. The run time and memory requirements of the reporting program are limiting us to top talkers and listeners right now, so no, we can't add source and destination ports to the report.
DNS updates for registered hosts
For quite a long time, users with newly-registered computers had to wait up to six hours for those new registrations to be reflected in the campus DNS servers. The update process was overly conservative, to avoid losing any data, and took too long to be run more frequently.
The old process also left a short window when a particular hostname could be unresolvable -- it removed all old hostnames, then added them back in batches. There was a period between a hostname's removal and its readdition that the hostname would be unknown by the campus name servers.
The update process was recently rewritten -- it is now much faster and does not remove hosts whose IP address and hostname remain the same. Since it's faster, it can be run every hour, so users have to wait no more than 60 minutes to see a newly-registered host in the DNS.