I have just installed FreeBSD 8.2 with sshd daemont during installation therefore version is:
# sshd -v
OpenSSH_5.4p1_hpn13v11 FreeBSD-20100308, OpenSSL 0.9.8q 2 Dec 2010
According to my task I have upgrade sshd to 6.0. I tried to upgrade it from ports /usr/ports/security/openssh-portable but current version port is 5.8.
OpenSSH installed as part of FreeBSD is under /usr with configuration under /etc/ssh. OpenSSH installed via the ports tree is under /usr/local with configuration under /usr/local/etc/ssh. Therefore rc.conf to have sshd_enable="NO" and openssh_enable="YES". Run /etc/rc.d/sshd forcestop and /usr/local/etc/rc.d/openssh start.
So, coming back to my task. First of all download tar with needed version.
#wget ftp://ftp.openbsd.org/pub/OpenBSD/OpenSSH/portable/openssh-6.0p1.tar.gz
# tar xvzf openssh-6.0p1.tar.gz
# cd openssh-6.0p1
# ./configure --prefix=/usr --sysconfdir=/etc/ssh --with-pam --with-ssl-dir
# make
#make install
Now just restart daemon
# /etc/rc.d/sshd restart
and check version
# sshd -v
OpenSSH_6.0p1, OpenSSL 0.9.8q 2 Dec 2010
