Cannot remove DN node from my cluster

When I use ‘nodetool removenode’ to remove a DN node from my cluster(with 143 nodes and scylla version 5.1.15), I encountered an error and the node failed to be removed finally.
Here is the error message:

[HOSTNAME-01 /]# nodetool status | grep DN
DN   5.03 TB    256          ?       f17b8181-ff05-4499-a6de-5f5225a9f50e  DC_rack
[HOSTNAME-01 /]# nodetool removenode f17b8181-ff05-4499-a6de-5f5225a9f50e
nodetool: Scylla API server HTTP POST to URL '/storage_service/remove_node' failed: seastar::rpc::remote_verb_error (node_ops_cmd_check: Node rejected node_ops_cmd=removenode_abort from node= with ops_uuid=c51ebd9a-2aaf-4c2e-bfad-c55567e23a39, pending_node_ops={}, the node ops is unknown)

I’m curious why does this happen and how can I solve this problem.

I see it in the code because the obtained ops_uuids is empty, but the command is correct. Is this a bug?

I don’t know what that means. @Asias_He?

In any case, this may be a bug that was fixed in later releases, 5.1 is not supported anymore.