---
# System prepended metadata

title: Excalibur

---

### How to SSH to Excalibur:
1. Make sure you are on [internal-cl](https://www.cst.cam.ac.uk/local/sys/network/wireless) network
2. Install Kerberos `sudo apt install krb5-kdc krb5-admin-server`
3. Follow https://www.cst.cam.ac.uk/local/sys/ssh
4. `kinit <raven_id>@DC.CL.CAM.AC.UK`
5. Password for <raven_id>@DC.CL.CAM.AC.UK: ############ (This has to be a special password provided by the department)
6. Now that you have the kerberos token assigned for you, do: 
    ```
    ssh -K <raven_id>@excalibur.cl.cam.ac.uk
    ```
7. To create a scratch directory, run: `sudo cl-mkscratchdir`
8. However, the scratch directory will be created at `/local/scratch/<username>`. To create a shortcut of the directory in your user, `cd ~/<username>`
9. Then run: `ln -s <from> <to>`
10. To check the size of your scratch directory, run: `df /local/scratch`

#### How to copy files from your laptop to Excalibur
```
scp -r -o GSSAPIDelegateCredentials=yes -o GSSAPIAuthentication=yes 
```
Example of From laptop to Excalibur: 
```
scp -r -o GSSAPIDelegateCredentials=yes -o GSSAPIAuthentication=yes ksanim@128.232.86.55:/home/ksanim/projects/ros2_sanity_ws/missions/Non_equivariant_configuration .
```

#### SET UP YOUR Scratch directory with all the necessary packages:
1. Set up SSH keygen
