There are a few different ways to restart a Nexus server, depending on how it was installed and how it is being run. Here are a few options:

1. If Nexus is running as a service on your system, you can use the systemctl command to stop and start the service. For example:

sudo systemctl stop nexus
sudo systemctl start nexus

2. If Nexus is running in a standalone mode, you can use the nexus.rc script to stop and start the server. For example:

./nexus.rc stop
./nexus.rc start

3. If Nexus is running in a Docker container, you can use the docker stop and docker start commands to stop and start the container. For example:

docker stop nexus
docker start nexus

Keep in mind that restarting the Nexus server will interrupt any ongoing tasks and may cause temporary service disruptions. It is generally a good idea to plan a restart during a maintenance window or at a time when it will have the least impact on your users.