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Administration and Management
The following combination is invalid:
The following combination is valid:
If there is any error at all (e.g., parsing error, invalid IP address, more than 20
characters in the write community string), the repeater configuration update
stops without making any updates. Since the serial COM port uses the
XMODEM protocol, it cannot indicate an error. Therefore, the UTP port status
LED's provide error indications. If the configuration file update is successful,
the status LED's flash green-off-green (0.5 second each). If an error is detected,
the status LED's flash orange-off-orange (0.5 second each).
If there is an active SLIP session on the COM serial port, there is a 3-minute
time-out before an XMODEM transfer can begin. When an XMODEM transfer
starts, the repeater disables all interrupts except for the timer. The CPU polls the
COM serial port for activity. Consequently, SNMP requests, as well as normal
repeater processing (e.g., checking for backup ports, updating the status LEDs),
are ignored during XMODEM transfers.
When the repeater (receiver) is ready to initiate an XMODEM transfer, it issues
a synchronization byte at 10-second intervals to the workstation (sender) to
inform it which type of block error checking method is used (CRC or
checksum). Once the error checking type is established, the repeater uses the
first XMODEM packet to synchronize the transfer and then discards the packet.
This causes the repeater to retransmit the first packet. The retransmission is
invisible to the user except in XMODEM applications that report block errors.