Source:  AURP-5.10

Explanation:  The router could not acquire sufficient packet receive buffers, also called Event Control Blocks (ECBs). AURP was trying to retransmit a packet when the ECB allocation error occurred. This could be a temporary condition or it could indicate that the number of ECBs available is not sufficient to support the server load.

Action:  If you consistently obtain ECB allocation errors, refer to Error Codes documentation.