IPv6 and NetworkManager - users - Fedora Mailing-Lists

Monday, 25 April 2016

On most of the networks where I have hosts, the Ethernet interface has 
an inet6 address with a 64 bit netmask and flags "scope global 
noprefixroute dynamic."

On a Comcast Business network, though, my hosts have one inet6 address 
with a 64 bit netmask and the same flags, plus another inet6 address 
with a 128 bit netmask and flags "scope global dynamic."

Testing shows that these hosts use the address with the 128 bit netmask 
by default as the source address for outbound connections.

I'm a little confused about the details here.  Why are my hosts getting 
multiple addresses with different prefixes?