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Re: ssh forwarding behaviour ipv6 and localhost?

Ian Malone wrote:
> I upgraded to FC6 over the weekend and found that my normal
> port forwarding trick to get Samba access to my home machine
> through a proxy stopped working, before I had something like
> this (running cygwin ssh):
> ssh -L ian 10 0 0 1 -f -N -i somekey
> (The strange forwarding from is to overcome the
> fact that Windows will only try this port for Samba. The
> login at is because I have to forward ssh over a proxy).
> But this started giving me connection refused messages.
> Trying Putty gave the same result, I also had a go at
> localhost instead to see if I'd done something funny to my
> hostname. No success. However, using explicitly
> works:
> ssh -L ian 10 0 0 1 -f -N -i somekey
> Is fine, what I want to know is does this have something to
> do with IPV6?  Either somewhere in samba or in sshd?
> $ cat /etc/hosts
> # Do not remove the following line, or various programs
> # that require network functionality will fail.
> ::1     atlas.millroad  atlas   localhost.localdomain   localhost

As you've found, "localhost" by default points at an IPv6 address on
Fedora (the IPv6 equivalent of This works for many things,
but not everything.

A bit of googling suggested:
  Traditionally, Samba and Microsoft Windows have run SMB on top of the
  NetBIOS protocol. On the Internet, NetBIOS can be layered on top of
  TCP and UDP using ports 137, 138, and 139. This is called
  NetBIOS-over-TCP, or NBT for short, and is essentially a giant hack by
  Microsoft to make their old legacy networking protocols run on TCP/IP.
  Since IPv4 addressing is deeply embedded in NBT, it will probably
  never be possible to run NetBIOS on IPv6, but this is probably for the
  -- http://www.litech.org/samba/

So yes, you're right -- blame IPv6.

Personally, I switched back to an IPv4 alias for localhost almost


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