Notes and Constraints

DMS for RabbitMQ has the following constraints, as listed in Table 1.

**Table 1** RabbitMQ usage constraints
Item	Constraint	Description
Version	3.7.17	AMQP 0-9-1 clients are supported.
Number of connections	The allowed number of connections differs by instance specifications and mode (single-node or cluster). For details, see Specifications.	-
Channels	≤ 2047	Number of channels that can be created for a single connection.
Message size	≤ 50 MB per message	Do not send a message larger than 50 MB. Otherwise, the message will fail to be created.
Memory high watermark	≤ 40%	If the memory usage exceeds 40%, the high memory watermark is triggered, blocking publishers.
Disk high watermark	≥ 5 GB	If the remaining disk space is less than 5 GB, the high disk watermark is triggered, blocking publishers.
cluster_partition_handling	pause_minority	When a network partition occurs in a cluster, cluster brokers will determine whether they are in a minority, that is, fewer than or equal to the total number of brokers. Minority brokers pause when a partition starts, detect the network status periodically, and start again when the partition ends. If queue mirroring is not enabled, queue replicas in the minority will no longer be available for message creation and retrieval. This strategy sacrifices availability for data consistency.
rabbitmq_delayed_message_exchange	There may be an error of about 1%. The actual delivery time may be earlier or later than the scheduled delivery time.	Whether delayed message delivery is enabled for the instance