[Pkg-exim4-users] Exim4 saying network unreachable. Why, nothings changed

[Nate Homier]

Error;

2016-11-06 07:36:04 1c3OXG-0005zy-2n H=gmail-smtp-in.l.google.com
[2607:f8b0:400e:c05::1a] Network is unreachable


Then;

2016-11-06 07:36:05 1c3OXG-0005zy-2n => *@gmail.com R=dnslookup
T=remote_smtp H=gmail-smtp-in.l.google.com [173.194.203.26]
X=TLS1.2:ECDHE_RSA_CHACHA20_POLY1305:256 CV=yes
DN="C=US,ST=California,L=Mountain View,O=Google Inc,CN=mx.google.com"
C="250 2.0.0 OK 1478442965 yi4si22465348pac.256 - gsmtp"


Sorta looks like an IPv6 address is failing. I'm confused as I have
never seen this error before. I am on a IPv4 network. Did Exim4 start
doings things differently? I tried telnetting into a remote host on
port 25 and it worked. So I have port 25 access to the world outside.
So far my server can send emails. It won't receive emails by design due
to mx settings.


dc_eximconfig_configtype='internet'
dc_other_hostnames='frontier'
dc_local_interfaces='127.0.0.1 ; ::1'
dc_readhost=''
dc_relay_domains=''
dc_minimaldns='false'
dc_relay_nets=''
dc_smarthost=''
CFILEMODE='644'
dc_use_split_config='false'
dc_hide_mailname=''
dc_mailname_in_oh='true'
dc_localdelivery='mail_spool'

***@frontier:~$ lsb_release -a
No LSB modules are available.
Distributor ID: Ubuntu
Description: Ubuntu 16.10
Release: 16.10
Codename: yakkety

***@frontier:~$ uname -a
Linux frontier 4.8.0-26-generic #28-Ubuntu SMP Tue Oct 18 14:39:52 UTC
2016 x86_64 x86_64 x86_64 GNU/Linux

It's probably harmless.

Nate.

[Nate Homier]

Now that I know it's harmless it's no big deal. Probably the router as
it's IPv6 aware. Oh well, no biggie.

Thanks, Nate.

***@frontier:~$ ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN
group default qlen 1
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: enp0s31f6: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc
pfifo_fast state UP group default qlen 1000
link/ether 40:8d:5c:57:b1:71 brd ff:ff:ff:ff:ff:ff
inet 192.168.0.100/24 brd 192.168.0.255 scope global enp0s31f6
valid_lft forever preferred_lft forever
inet6 fe80::428d:5cff:fe57:b171/64 scope link
valid_lft forever preferred_lft forever
3: wlp10s0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc mq state
DOWN group default qlen 1000
link/ether 7c:5c:f8:19:fb:e0 brd ff:ff:ff:ff:ff:ff

Post by Nate Homier
2016-11-06 07:36:04 1c3OXG-0005zy-2n H=gmail-smtp-in.l.google.com
[2607:f8b0:400e:c05::1a] Network is unreachable
Then;
T=remote_smtp H=gmail-smtp-in.l.google.com [173.194.203.26]
X=TLS1.2:ECDHE_RSA_CHACHA20_POLY1305:256 CV=yes
DN="C=US,ST=California,L=Mountain View,O=Google
Inc,CN=mx.google.com" C="250
2.0.0 OK 1478442965 yi4si22465348pac.256 - gsmtp"

Your Exim tries IPv6, fails, and then tries IPv4, successfully.
The output of "ip addr" and/or "ip -6 route" might give hints why
your
exim thinks that it has IPv6 connectivity.

Post by Nate Homier
Sorta looks like an IPv6 address is failing. I'm confused as I have
never
seen this error before. I am on a IPv4 network. Did Exim4 start
doings
things differently? I tried telnetting into a remote host on port
25 and it
worked. So I have port 25 access to the world outside. So far my
server
can send emails. It won't receive emails by design due to mx
settings.

It might also be the case that your recipient has started listing an
AAAA record for its MX.
Greetings
Marc