I have the following ipfw settings on my Mac OS X 10.4 Tiger:
00100 allow ip from any to 126.96.36.199 00110 allow tcp from any to 188.8.131.52 00120 allow udp from any to 184.108.40.206 00130 allow ip from 220.127.116.11 to any 00140 allow tcp from 18.104.22.168 to any 00150 allow udp from 22.214.171.124 to any 65534 deny ip from any to any 65535 allow ip from any to any
I am trying to ssh to the Mac from a Linux computer which has IP address 126.96.36.199, and sshd is running on the Mac. However, the ssh client outputs the following:
ssh firstname.lastname@example.org -v OpenSSH_5.5p1, OpenSSL 1.0.0d-fips 8 Feb 2011 debug1: Reading configuration data /etc/ssh/ssh_config debug1: Applying options for * debug1: Connecting to mac.example.com [10.10.10.10] port 22. debug1: Connection established. debug1: identity file /home/me/.ssh/id_rsa type -1 debug1: identity file /home/me/.ssh/id_rsa-cert type -1 debug1: identity file /home/me/.ssh/id_dsa type -1 debug1: identity file /home/me/.ssh/id_dsa-cert type -1 ssh_exchange_identification: Connection closed by remote host
What could cause the Mac to suddenly close the connection before even asking for a password?
I believe it has to do with the IPFW settings, because the ssh worked when I simply had
65535 allow ip from any to any as the IPFW settings. E.g., do I need a rule for a reverse DNS lookup?