127.0.1.1 breaks 3partysw license managers

[alexp]

127.0.1.1 zippy zippy.mit.edu
is denied, but
127.0.1.1 zippy.mit.edu
is allowed.

This probably happens because hostname -i will be 127.0.1.1 in the
former case, but 18.142.4.128 in the latter case. So this is another
manefestation of the known problem with 127.0.1.1.

Thanks for the information; we really need to solve the problem though; do
we do that by making sure all hosts on those lines are fully qualified?

To be clear, the problem is not that there is a non-fully-qualified
hostname in /etc/hosts. The problem is that because your kernel’s
hostname is zippy, which is resolved by /etc/hosts to 127.0.1.1, license
managers that have a client-side ACL of IP addresses (like 18.*) get
confused.

If, as you did, you take zippy out of /etc/hosts (leaving only
zippy.mit.edu), then zippy is resolved by DNS to 18.142.4.128 using the
search path and servers in /etc/resolv.conf, and the license manager
presumably becomes less confused.

A better client-side workaround is to put the right IP address in
/etc/hosts:

18.142.4.128 zippy zippy.mit.edu

which is what I think the Ubuntu installer does if you configure it with a
static IP address at install time. (For the cluster machines, we
currently don’t.)

We are currently discussing possible solutions on zephyr.