IPv6 and packet sending

[Alan Buxey]

Hi,

> > in my proxy.conf I have a FQDN for a proxy destination.
> 
>   That's generally a bad idea, but OK...

ah really? okay - I can dig that (no pun intended honest!) - it
best practice is to use the IPv4/IPv6 address instead then I can go 
that way.

>   What does that mean?  It *prefers* IPv4.  But if a FQDN has *only* an
> IPv6 record, it will use that.

I'd already tested that theorem and found that yes, if it only had a AAAA
then it'd get used.

>   Which RFC?  Not any of the RADIUS ones, IIRC.

its a more general protocol thing and not a specific one:


RFC 3484 - Default Address Selection for Internet Protocol version 6 (IPv6)


in particular 10.3 - "This means that applications will use IPv6 in
   preference to IPv4 when the two are equally suitable"

this statement has been, over the past few years, found to be generally true
for other services and daemons... which was why what I found earlier
this week with FR was a little peculiar.

alan