Das scheint ein DNS-Problem zu sein (hatte ich auch schon, da hat es ebenfalls immer ca. 1 Minute gedauert). Hat der Server vollen DNS-Zugriff?
Welche sshd-Version benutzt Du?
Eine Option "CheckIP" gibt es übrigens nicht. Für den Client gibt es eine Option "CheckHostIP" (meintest Du die?). Die ist für Dein Problem aber nicht relevant, denn es dürfte am Server liegen.
Es gibt "ReverseMappingCheck" für den SSH-Daemon (standardmäßig aber auf "no" eingestellt). Schau mal auf dem Server in /etc/ssh/sshd_config nach, was dort eingestellt ist.
ReverseMappingCheck
Specifies whether sshd should try to verify the remote host name
and check that the resolved host name for the remote IP address
maps back to the very same IP address. The default is ``no''.
# Package generated configuration file
# See the sshd(8) manpage for defails
# What ports, IPs and protocols we listen for
Port 22
# Use these options to restrict which interfaces/protocols sshd will bind to
#ListenAddress ::
#ListenAddress 0.0.0.0
Protocol 2
# HostKeys for protocol version 2
HostKey /etc/ssh/ssh_host_rsa_key
HostKey /etc/ssh/ssh_host_dsa_key
#Privilege Separation is turned on for security
UsePrivilegeSeparation yes
# ...but breaks Pam auth via kbdint, so we have to turn it off
# Use PAM authentication via keyboard-interactive so PAM modules can
# properly interface with the user (off due to PrivSep)
PAMAuthenticationViaKbdInt no
# Lifetime and size of ephemeral version 1 server key
KeyRegenerationInterval 3600
ServerKeyBits 768
# Logging
SyslogFacility AUTH
LogLevel INFO
# Authentication:
LoginGraceTime 600
PermitRootLogin yes
StrictModes yes
RSAAuthentication yes
PubkeyAuthentication yes
#AuthorizedKeysFile %h/.ssh/authorized_keys
# rhosts authentication should not be used
RhostsAuthentication no
# Don't read the user's ~/.rhosts and ~/.shosts files
IgnoreRhosts yes
# For this to work you will also need host keys in /etc/ssh_known_hosts
RhostsRSAAuthentication no
# similar for protocol version 2
HostbasedAuthentication no
# Uncomment if you don't trust ~/.ssh/known_hosts for RhostsRSAAuthentication
#IgnoreUserKnownHosts yes
# To enable empty passwords, change to yes (NOT RECOMMENDED)
PermitEmptyPasswords no
# Uncomment to disable s/key passwords
#ChallengeResponseAuthentication no
# To disable tunneled clear text passwords, change to no here!
PasswordAuthentication yes
# To change Kerberos options
#KerberosAuthentication no
#KerberosOrLocalPasswd yes
#AFSTokenPassing no
#KerberosTicketCleanup no
# Kerberos TGT Passing does only work with the AFS kaserver
#KerberosTgtPassing yes
X11Forwarding no
X11DisplayOffset 10
PrintMotd no
#PrintLastLog no
KeepAlive yes
#UseLogin no
#MaxStartups 10:30:60
#Banner /etc/issue.net
-------> ReverseMappingCheck no <---------------
Subsystem sftp /usr/lib/sftp-server
SUN Sparc Server 10 (2x 75 MHz) We have joy, We have fun, We run Linux on a SUN.
