As you can see in the log there is some weird behavior during one build which node selection: "on server" in master step and "on node running parent step (or server)" on all child steps.
Suddenly the build switches the node where the build is running, leading to some weird null check failure.
Could you please have a look if there is something suspicious in the node selection. Sadly it is very hard to reproduce or trace the problem.
Description
As you can see in the log there is some weird behavior during one build which node selection: "on server" in master step and "on node running parent step (or server)" on all child steps.
Suddenly the build switches the node where the build is running, leading to some weird null check failure.
Could you please have a look if there is something suspicious in the node selection. Sadly it is very hard to reproduce or trace the problem.