Avanti provides DE435 and DE500 virtual NIC identities. Historical field guidance recommends DE435 for OpenVMS releases before V7.2 because some older configurations encountered DE500 startup problems. Current retained-firmware evidence verifies selected DE435 operation but does not establish V7.2 as a universal DE500 boundary or reproduce the workaround below. Prefer DE435 for an untested older guest unless release-matched OpenVMS documentation and a controlled test establish DE500 support.

If an older guest must use DE500 and DECnet or TCP/IP does not start, preserve the exact console output before testing the following historical sequence on a recoverable copy. The original error signature behind this field guidance was not retained, so treat the sequence as a diagnostic experiment for network-service startup failure, not as a known fix for an identifiable error. Do not apply it to unrelated network failures.

•Use the DE500 21143 NIC definition in the Avanti configuration file.

•Adapt the following sequence to the DECnet and TCP/IP products installed on that guest. Do not copy it unchanged into a production startup procedure.

$ @SYS$MANAGER:STARTNET.COM        !Start DECnet
$ MC NCP SET EXEC STAT OFF        !Shut down DECnet
$ WAIT 00:00:10                        !Pause 10 seconds*
$ @SYS$MANAGER:STARTNET.COM        !Restart DECnet
⁞
$ @SYS$STARTUP:UCX$STARTUP.COM        !Start TCP/IP services

The ten-second delay and reported NETNOSTATE bug check are historical observations, not qualified timing requirements. Validate DECnet and TCP/IP after a controlled reboot, and remove the sequence if it does not address the recorded failure.