# Updating software

- Backup the SD card image for larger upgrade → see [High Endurance Micro-SDHC card 32 GB 100 MB/s UHS Class 3 by SANDISK](https://wiki.stadtfabrikanten.org/books/trikarus-project-hangprinter/page/ceiling-module-high-endurance-micro-sdhc-card-32-gb-100-mbs-uhs-class-3-by-sandisk "Ceiling Module |  High Endurance Micro-SDHC card 32 GB 100 MB/s UHS Class 3 by SANDISK")
- Update Repetier Server (using software frontend)
- Update Grafana → use `/opt/upgrade-grafana.sh` script

```bash
apt update
apt upgrade

#fix some broken keys if required:
curl -sS https://dl.yarnpkg.com/debian/pubkey.gpg | sudo apt-key add -

#An error occurred during the signature verification. The repository is not updated and the previous index files will be used. GPG error: http://deb.debian.org/debian unstable InRelease: The following signatures couldn't be verified because the public key is not available: NO_PUBKEY 648ACFD622F3D138 NO_PUBKEY 0E98404D386FA1D9
sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 648ACFD622F3D138
```