[LU-13001] check_routers_before_use causes LNet to hang indefinitely if any router is down

• Type: Bug
• Resolution: Fixed
• Priority: Major
• Fix Version/s: Lustre 2.14.0
• Affects Version/s: Lustre 2.13.0, Lustre 2.14.0
• Severity: 3
• Assignee: Chris Horn
• Reporter: Chris Horn

Description

Historically, check_routers_before_use would cause LNet
initialization to pause until all routers had been ping'd once.

This behavior was changed in commit
fe17e9b8370affe063769b880f02b9190584baaa from LU-11298. Now, LNet
will wait indefinitely until discovery completes on all routers.
This is problematic, because if even one router is down then LNet
will stall forever.