add `docs/linux.md`

docs/linux.md

+# Installing Ollama on Linux
+
+> Note: A one line installer for Ollama is available by running:
+>
+> ```
+> curl https://ollama.ai/install.sh | sh
+> ```
+
+## Download the `ollama` binary
+
+Ollama is distributed as a self-contained binary. Download it to a directory in your PATH:
+
+```
+sudo curl -L https://ollama.ai/download/ollama-linux-amd64 -o /usr/bin/ollama
+```
+
+## Install CUDA drivers (optional for Nvidia GPUs)
+
+[Download and install](https://developer.nvidia.com/cuda-downloads) CUDA.
+
+Verify that the drivers are installed by running the following command, which should print details about your GPU:
+
+```
+nvidia-smi
+```
+
+## Adding Ollama as a startup service
+
+Create a user for Ollama:
+
+```
+sudo useradd -r -s /bin/false -m -d /usr/share/ollama ollama
+```
+
+Create a service file in `/etc/systemd/system/ollama.service`:
+
+```ini
+[Unit]
+Description=Ollama Service
+After=network-online.target
+
+[Service]
+ExecStart=/usr/bin/ollama serve
+User=ollama
+Group=ollama
+Restart=always
+RestartSec=3
+Environment="HOME=/usr/share/ollama"
+
+[Install]
+WantedBy=default.target
+```
+
+Then start the service:
+
+```
+sudo systemctl daemon-reload
+sudo systemctl enable ollama
+```
+
+## Run a model
+
+```
+ollama run llama2
+```