Alternate Exchange If messages to this exchange cannot otherwise be routed, send them to the alternate exchange named here. Message deduplication Enable deduplication for this exchange | Deduplication cache size Deduplication cache size, in number of entries | Deduplication cache ttl How long an entry lives in the deduplication cache, in milliseconds | Deduplication header Which header to check for deduplication, defaults to x-deduplication-header