Systemd implementation of autossh.

1 files changed, 41 insertions, 0 deletions

diff --git a/autossh/systemd/system/autossh@.service b/autossh/systemd/system/autossh@.service
new file mode 100644
index 0000000..2f4d5f3
--- /dev/null
+++ b/autossh/systemd/system/autossh@.service
@@ -0,0 +1,41 @@
+# systemd implementation of autossh
+#
+# On $CLIENT
+#  * Create keypair (no passphrase):
+#    ssh-keygen -t ed25519 -f ~/.ssh/id_ed25519_$SERVER
+#  * Show pubkey:
+#    cat ~/.ssh/id_ed25519_$SERVER.pub
+#
+# On $SERVER
+#  * Create locked-down user
+#    adduser --system --group --force-badname $CLIENT
+#  * Accept connections from $CLIENT (copy pubkey from above):
+#    su - olav.jones.dk -c "mkdir -p ~/.ssh"
+#    su - olav.jones.dk -c "echo '$PUBKEY' > ~/.ssh/authorized_keys"
+#
+# On $CLIENT
+#  * Test (and approve) connection to $SERVER:
+#    ssh -i /root/.ssh/id_ed25519_$SERVER $CLIENT@$SERVER
+#  * Copy this file to /etc/systemd/system/autossh@.service
+#  * Register with systemd, activate, and verify:
+#    systemctl enable autossh@$SERVER
+#    service autossh@$SERVER start
+#    service autossh@$SERVER status
+#
+# On $SERVER
+#  * Locate port:
+#    lsof -nai TCP -a -u olav.jones.dk
+#  * Connect:
+#    ssh -p $PORT 127.0.0.1
+
+[Unit]
+Description=SSH tunnel for %i
+
+[Service]
+Type=simple
+Restart=always
+RestartSec=1min
+ExecStart=/usr/bin/ssh -i /root/.ssh/id_ed25519_%i -o BatchMode=yes -o ExitOnForwardFailure=yes -o IPQoS=lowdelay -o ServerAliveInterval=10 -CNR 0:127.0.0.1:22 %H@%i
+
+[Install]
+WantedBy=multi-user.target