根据搜索到的资料，找到了这里:
luo[~]ssh [email protected]192.168.100.233 Press ^@ (C-Space) to enter file transfer mode, then ? for help [email protected]192.168.100.233‘s password: Welcome to Linux Mint 18.3 Sylvia (GNU/Linux 4.13.0-36-generic x86_64) * Documentation: https://www.linuxmint.com Last login: Sat Mar 3 14:09:53 2018 from 192.168.100.233 luo[~]tail /etc/update-motd.d/00-header # 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. [ -r /etc/lsb-release ] && . /etc/lsb-release if [ -z "$DISTRIB_DESCRIPTION" ] && [ -x /usr/bin/lsb_release ]; then # Fall back to using the very slow lsb_release utility DISTRIB_DESCRIPTION=$(lsb_release -s -d) fi printf "Welcome to %s (%s %s %s)\n" "$DISTRIB_DESCRIPTION" "$(uname -o)" "$(uname -r)" "$(uname -m)" luo[~]cat /etc/lsb-release DISTRIB_ID=LinuxMint DISTRIB_RELEASE=18.3 DISTRIB_CODENAME=sylvia DISTRIB_DESCRIPTION="Linux Mint 18.3 Sylvia"
随后，又对 motd 进行了进一步了解。发现，ubuntu 下执行 motd 的其实是一个叫 updatemotd 的框架，也就是实际打印上面内容的地方。
比如：https://wiki.ubuntu.com/UpdateMotd
版本不一样，动作也有区别，但是，基本就是 motd 的范畴就对了。