write basic ssh

networking/ssh.md

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+---
+title: "ssh"
+tags: [ "networking" ]
+---
+# Basic `ssh`
+
+Try out basic ssh by accessing `git.charm.sh`, without needing authentication:
+
+
+```bash
+ssh git.charm.sh
+```
+
+Start an ssh server to try it out.
+The ssh server is sometimes in a package called `openssh`, and sometimes only in `openssh-server`.
+
+Once it's installed, check it's working:
+
+```bash
+sudo systemctl status ssh
+```
+
+If that doesn't work, the service may be called `sshd`.
+
+```bash
+sudo systemctl status sshd
+```
+
+Then start that service:
+
+```bash
+sudo systemctl start sshd
+```
+Test it works by using ssh into your own system, from inside:
+
+
+```bash
+ssh $USER@localhost
+```
+
+Access the computer from another computer on the same local network by finding your computer's IP address.
+
+
+```bash
+ip address | grep inet
+```
+
+Here is mine:
+
+
+> inet 127.0.0.1/8 scope host lo
+> 
+> inet6 ::1/128 scope host noprefixroute
+> 
+> inet 192.168.0.12/24 brd 192.168.0.255 scope global dynamic noprefixroute en
+
+
+The first one starts `127`, which means it returns back to that computer (like `localhost`).
+The second is an ipv6 address, which is too angelic for this world, and has yet to ascend.
+The third will work from a remote computer.
+
+
+```bash
+ssh $USERNAME@IP_ADDRESS
+```
+
+Once you have that, generate some ssh keys:
+
+```bash
+ssh-keygen
+```
+
+Look at your keys:
+
+
+```bash
+ls ~/.ssh
+```
+
+You can share the one ending in `.pub` freely.
+The other is secret.
+
+Now send those keys to a remote computer:
+
+```bash
+ssh-copy-id $USERNAME@IP_ADDRESS
+```
+
+Now you can log in without a password.