I'm trying to update a series of ntp.conf files, which have lines like the following, followed by what it should change to (brackets show the strings may or may not be there):

server old-ip-or-hostname-here prefer [burst iburst]
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change to:

server new-ip-here prefer burst iburst  

 
server another-ip-or-hostname-here [burst iburst]
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change to:

 
nothing (remove the line)
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as well as, in some cases,

server 127.127.1.0
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occurs, and it should be leave as is, i.e. no change.

So, I try the following for the first:

perl -p -i -e 's/server [\w\.]+ prefer.*/server new-ip-here prefer bur
+st iburst/g' ntp.conf
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but I'm not sure how to write the regexp for the second without removing lines for 127.127.1.0.

I'm running this from a shell script, so to keep it simple, I'd like to keep it as a perl one-liner. Also, for the second replacement, it could be pretty much any IP address or hostname; I'd rather not go through all my systems to build a regexp of all the possible values.

Any thoughts on how to write the second regexp?