I am trying to run a linux high availability cluster (failover pair) using serial as one of the heartbeats. Due to numerous serial over-runs the systems are actually crashing periodically. This is a very frustrating development for a system intended to provide HA. (certainly not ha ha ha). I have updated to the latest bios. I have checked RTS DTS XON XOFF etc. This is happening with the stock and custom kernels. This is happening on three pairs of servers. The serial ports are detected as: Serial: 8250/16550 driver $Revision: 1.90 $ 32 ports, IRQ sharing enabled serial8250: ttyS0 at I/O 0x3f8 (irq = 4) is a 16550A Any advice would be greatly appreciated. Thank you. <><Randy <><Randall Grimshaw Room 203 Machinery Hall Syracuse University Syracuse, NY 13244 315-443-5779 rgrimsha@xxxxxxx