Guide to enable ssh on macOSX Recovery Mode

Boot in recovery mode

• https://www.lifewire.com/restart-a-mac-into-recovery-mode-5184142

Open Terminal

Go to Utility -> Terminal

Create a writeable ramdisk:

The root account has a random password. And you can’t reset it, since the filesystem is read-only. Use Pubkey authentication!

rdsize=$((16*1024*1024/512)) # 16 megabytes
dev=`hdik -drivekey system-image=yes -nomount "ram://$rdsize"`
echo $?; echo $dev # check for errors!
newfs_hfs $dev
eval `/usr/bin/stat -s /var/root` # store perms for old mountponit
mount -t hfs -o union -o nobrowse $dev /var/root # magic happens here
chown "$st_uid:$st_gid" /var/root
chmod "$st_mode" /var/root

Next, add your key to /var/root/.ssh/authorized_keys.

mkdir /var/root/.ssh
vim /var/root/.ssh/authorized_keys

Generate SSH KEY for the server

ssh-keygen -t rsa

Runs sshd

/usr/sbin/sshd -d -o UsePAM=no -h /var/root/.ssh/id_rsa

Connect from client

ssh root@<ip>

Contribute

Thanks to your contributions!

Here is a list of users who already contributed to this repository:

References

• https://bennettp123.com/2014/06/09/os-x-recovery-shenanigans/
• https://www.ssh.com/academy/ssh/sshd
• https://itectec.com/askdifferent/macos-how-to-open-the-sshd-service/

Author

(c) 2021 Valentino Lauciani vlauciani[at]gmail.com