Thanks to Jess Keating for the information abut NFS failures.
Unfortunately, I can't seem to make FTP or HTTP installs work on my machines. (I suspect a marginal memory stick in the server.) The FTP and HTTP downloads fail and there is no time-out detection in anaconda or the get URL process to retry when they do fail.
I'll try memory testing again on the server, but memtest86+ doesn't seem to catch the problem. Running SETI@Home or other math processes can lock the machine up quite reliably. I just hate marginally operative hardware!
Even if it is a problem with my server, I think anaconda should attempt to detect time-outs and retry.
--Wolfe