Basically SonicWall firewall is able to support all the protocols which listed under Network -> Services. By default, not all the protocols, which including SCTP, are listed there.
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So you need to define a customer service object to let the firewall knows the protocol. Otherwise, SCTP packets will be dropped as Unknow Protocol.
To do that, go to Network -> Services, click Add under Service Objects tab, Add Service window will display. Follow the configuration as below. Then click OK.
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