SSH: Agent Admitted Failure To Sign...

When you encounter error message of "SSH: Agent Admitted Failure To Sign..." with your new ssh key, just simply log off current session and re-login again.

Another way to fix this issue within the current session is to type # ssh-add, then the new key will be added to ssh-agent.

REFERENCE:
http://www.cyberciti.biz/faq/unix-appleosx-linux-bsd-agent-admitted-failuretosignusingkey/

ssh port-forwarding in the background

$ ssh -fNL 2222:localhost:2222 pride

REFERENCE :
Lucas, M. W. SSH Mastery: OpenSSH, Tunnels and Keys

chmod -R 700 ~/.ssh for authorized_keys

permission of 700 may be required for correct setup of ssh key authorization!

chroot sftp & batch it!

1) edit /etc/ssh/sshd_config:

Match User backup

ChrootDirectory /var/backup

X11Forwarding no

AllowTcpForwarding no

ForceCommand internal-sftp

2) # kill -HUP `cat /var/run/sshd.pid`

3) create the new user, generate key,  and set permissions:

# mkdir -p /home/backup/.ssh

# useradd backup

# ssh-keygen -t dsa 

# cp id_dsa.pub /home/backup/.ssh/authorized_keys

# mkdir -p /var/backup/dir1

# chown root:wheel /var/backup

# chmod 755 /var/backup

# chown backup /var/backup/dir1

3) edit a batch file, sftp_batch  for sftp:

cd dir1

put myfile

4) then, fireup sftp client for batch processing now!

# sftp -b sftp_batch backup@localhost

REFERENCES:
http://www.howtoforge.com/chrooted-ssh-sftp-tutorial-debian-lenny

syslog to a remote central log host

# vi /etc/syslog.conf


*.notice;auth,authpriv,cron,ftp,kern,lpr,mail,user.none @loghost
auth,daemon,syslog,user.info;authpriv,kern.debug                @loghost

=> save then reboot!

Setting up ftpd

1) edit /etc/rc.conf as below then reboot, or:
ftpd_flags="-DllUSA" # for non-inetd use: ftpd_flags="-D"

2) manually fire up your ftpd:
# /usr/libexec/ftpd -DllUSA

3) edit files as below for setting up details of ftpd, such as welcome message, hostname, denied users, and site-wide nologin. Remember that ftp user shell should be set to /sbin/nologin.

/etc/ftpchroot (important!!)
/etc/shells
/etc/ftpwelcome
/etc/myname
/etc/ftpusers
/etc/nologin

REFERENCES:
http://www.tongatapu.net.to/nix/OpenBSD/ftpServer.htm
http://www.twbsd.org/cht/book/ch15.htm

access logging with pf

1) edit /etc/pf.conf, then run #pfctl -f /etc/pf.conf. Of course you also have to determine $ and <> variables first.


# Ignore IGMP log
# You can add this line if many IGMP packets bothering you.
pass in on $int_if proto igmp all allow-opts

# Port mapping

pass in log on $ext_if proto tcp from <access_list> to $ext_ip port 22 rdr-to $inside_server_ip port 22

2) view pf log as follows.

# tcpdump -n -e -ttt -r /var/log/pflog