The issue is caused by the `libhwloc` library, which is used by `OpenRTE` (the OpenMPI component) to explore the hardware topology of the node during the launch of parallel processes. When `hwloc_topology_load()` is called, `libhwloc` iterates over all of its available components, which are implemented as plug-ins. One of these components, `gl`, is responsible for gathering information about the system's graphics devices and uses X11 calls like `XOpenDisplay()`, which can generate the error message "Invalid MIT-MAGIC-COOKIE-1 key" if it fails to connect to the X11 server.
In many cases, this gl component is not needed on HPC clusters and can be safely disabled by setting the `HWLOC_COMPONENTS` environment variable to exclude it:
`export HWLOC_COMPONENTS="-gl"`
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