Accounting Retransmission Algorithm

The RADIUS client accounting software uses the standard back-off retransmission algorithm. Since accounting transactions generally do not require timeliness this algorithm focuses on redundancy rather than expediency. The highest priority server is always tried first regardless of past transaction history. Consider three accounting servers – 1, 2 and 3 each with the configurable number of retries set to 2:

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Accounting Retransmission Algorithm (No Servers Responding)

This figure shows the entire retransmission algorithm for a single RADIUS accounting transaction if none of the servers were to respond. All of the transactions to each of the servers are attempted before another server is attempted. If the initial server can handle the entire accounting transmission load, then all transactions will go to that server.