1. Viewing the status of the Application:
nex-cli apps:info my-app
If the App Details section "STATUS" is "active", and the Source Control Management section "LAST COMMIT" is correct, if so, your deployment should be ok & running.
If the status is "restarting" and it has beens some time, then it may be having troubles starting and is worth investigating the cubes.
2. Viewing the status of the cubes, and checking the logs
List the cubes for your app:
nex-cli cubes --app my-app --all
Most likely the cube that has crashed status will be "performing:starting".. SSH into the rack using the crashed cube's IP address:
nex-cli racks:ssh 10.0.1.234
Viewing the logs for the cube:
sudo su docker logs CUBE-INSTANCE-ID
3. Logs don't look like your new code has been applied?
Whilst ssh'ed in the rack, list the docker containers to check the status:
sudo su docker ps -a
If the status of the container with the same NAME as the crashed cube instance ID has exited hours or days ago, and you recently deployed, then the new code hasn't been applied properly.
4. Deleting the Nex! Locks & Restarting the Cubes
The lock files are used to control the state of actions currently undertaken on containers. If a containers crashes during provisioning the lock will stay there and the container will be forever considered as “starting” or “provisioning”.
SSH into the rack, and then delete the Nex! Locks:
rm -r /var/lock/nex/*
Scale applications down as many times as there are Cube
nex-cli apps:down my-app
After the apps:info status is "stopped" for all Cube Instances, scale apps up as many times are there are Cube Instances:
nex-cli apps:up my-app
When all Cubes apps:info status is "running", see if it's now working. If not, repeat these steps, especially viewing the crashed cube's logs as it may be different after it's restarted with the latest code.