A hardware server boots, but then freezes randomly after printing "
Trying to start UDEV", or a few seconds after displaying the login prompt.
Also, when booting the system with the kernel option "
debug silencelevel=8" and without
quiet, there are large timestamps (you can view log messages on the local console by switching to dedicated console using Alt-F12):
... [ 0.001000] Detected 2600.042 MHz processor. [18014398.509494] Calibrating delay loop (skipped), value calculated using timer frequency.. 5200.08 BogoMIPS (lpj=2600042) [18014398.509501] pid_max: default: 1048576 minimum: 301
There is no straightforward explanation for the problem and why a cold reboot helps. The situation occurs rarely.
The "18014398" seconds mark in the output above represents 2^64 nanoseconds, meaning the time-stamp counter in the CPU has a negative step that caused the overflow of the counter. This is most likely a hardware issuethat is not fixable by a warm reboot, e.g., BIOS does not reset CPUs properly.
A cold reboot fixes the issue, reinitializing everything properly.
Perform a cold reboot of the server; turn the power off, and in a few minutes, turn it on.