DSA keys have since been deprecated. Use the following command:

ssh -oHostKeyAlgorithms=+ssh-dss -oPubKeyAcceptedKeyTypes=+dsa user@x.x.x.x

more filename.extension | mailx user@domain.com

Mac:

1. Thunderbird > Preferences > Advanced > General > Config Editor
2. Search for mail.identity.default.suppress_signature_separator;
3. Right click and toggle to true

Windows

1. Tools > Options > Advanced > General > Config Editor
2. Search for mail.identity.default.suppress_signature_separator;
3. Double click on false to toggle to true

After setting the server time with the following command:

dpkg-reconfigure tzdata

The syslog service now needs restarted:

service syslog restart

Tail the mail.log to check the entries are stamped with the correct time:

tail -f /var/log/mail/log

If you are trying to packet capture on a remote server as a non root user carry out the following as root:

Add a capture group and add yourself to it:

groupadd pcap
usermod -a -G pcap nonrootuser

Next, change the group of tcpdump and set permissions:

chgrp pcap /usr/sbin/tcpdump
chmod 750 /usr/sbin/tcpdump

Finally, use setcap to give tcpdump the necessary permissions:

setcap cap_net_raw,cap_net_admin=eip /usr/sbin/tcpdump

Credit goes to askubuntu.com: http://askubuntu.com/questions/530920/tcpdump-permissions-problem