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I'm setting up some server but I stubbled into an issue with one server.

I setup a local dns server, and when I try to connect to this server with ssh I will get : Permission denied (publickey,keyboard-interactive).

But when I access it like alpha@ it works fine with Pubkey Auth. Strange part is when I connect to a server => a hostname managed by the dns server, it will connect fine when using the hostname.

I'm using a ubuntu 10.04 amd64 as base for all the server, they are actually identical images I took a snapshot from the bare minimum setup, so can't blame the OS.

I compared my sshd_config files but they are almost Identical, only the place of the authorized_keys is different, can't blame that full for giving problems.

Locally I removed my known_hosts related to the dns server and tried again without any luck.

This is a copy of my sshd_config file maybe someone spots a error:

Port                             22
Protocol                         2
HostKey                         /etc/ssh/ssh_host_rsa_key
HostKey                         /etc/ssh/ssh_host_dsa_key
UsePrivilegeSeparation          yes
LoginGraceTime                  20
PermitRootLogin                 no
RSAAuthentication               yes
RhostsRSAAuthentication         yes
HostBasedAuthentication         no
PubkeyAuthentication            yes
AuthorizedKeysFile              /etc/ssh/authorized_keys
PermitEmptyPasswords            no
PasswordAuthentication          no
StrictModes                     no
ClientAliveInterval             60
ClientAliveCountMax             0

# Host Specific !!!!!

# List of allowed users
AllowUsers                      alpha

# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 768

# Logging
SyslogFacility AUTH
LogLevel INFO

X11Forwarding yes
X11DisplayOffset 10
PrintMotd no
PrintLastLog yes
TCPKeepAlive yes
#UseLogin no

# Allow client to pass locale environment variables
AcceptEnv LANG LC_*

Does anyone countered the same problem? Or has some advise?

Thanks a lot in advance!

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Use "ssh -v" and you will see why. The problem is probably into your ssh_config (not into ssd_config) or because your ~/.ssh/know_host contain a wrong value. – Gregory MOUSSAT Apr 22 '12 at 21:43
You just set up a DNS server, and now youre saying that logging into a machine via its DNS hostname doesnt work, but via its IP does. Since you've been playing with DNS, start simple. Are you sure is resolving to – Patrick Apr 22 '12 at 23:22
Yes I can dig and nslookup it no problem using resolving the hostname – Niels Apr 23 '12 at 6:55
Do you have SELinux running? – Khaled Apr 23 '12 at 7:32
No I'm running ubuntu and as client mac os x. But I solved my issue apperently I needed to flush the dns cache on my mac with this command: dscacheutil -flushcache – Niels Apr 24 '12 at 8:45



Are you see ip?

I think you havenot problem with ssh, you have problem with dns.

What dns server are you use? (cat /etc/resolv.conf )

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