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[Bug 2029] New: ssh connection failure error message confusing when talking to dual IPv4/6 host

Priority: P5
Bug ID: 2029
Summary: ssh connection failure error message confusing when
talking to dual IPv4/6 host
Severity: normal
Classification: Unclassified
OS: Linux
Hardware: ix86
Status: NEW
Version: 5.9p1
Component: ssh
Product: Portable OpenSSH

I have a dual IPv4/6 server which has both A and AAAA records
published for it's primary domain name. I had just rebooted the
server for a kernel update and was trying to ssh back in. It failed
with a "network unreachable" error which was totally misleading. The
issue was that the server was slow to come up and was not listening
port 22 yet. The error message should have been "connection

During the period when I was waiting, if I used ssh directly to the
IPv4 address, I (correctly) got "connection refused". When I ssh'd
the IPv6 address I (also correctly) got network unreachable since
there is no IPv6 connectivity other than link-local on the network
ssh client was connecting from.

it looks like what ssh is doing in the case of a host with dual
records is looking them both up, trying both connections, and if the
case of both failing, it's returning the IPv6 error message. In this
case it was quite confusing as there's no indication it's an IPv6
connection the message is about. I was trying to figure out how I
could ping the server and at the same time have the network be

It would be better if, in the case of two errors, network unreachable
is only handed back to the user if no other error (such as connection
refused) does not indicate that the network was reachable and a
connection to the remote server made at some level.

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