How to Resolve Seata “can not register RM” Connection Errors

After completing the Seata server configuration, the business services fail to start because they cannot connect to the Seata server, showing error messages such as “0101 can not connect to ip:8091 cause: can not register RM, err: can not connect to services‑server” and “0304 can not connect to IP:8091 …”.

The root cause is the default.grouplist setting in file.conf. When the IP is set to localhost or 127.0.0.1 the error code is 0101; when an internal network IP is used the error code becomes 0304. The recommendation is to configure the address with an external (public) IP.

service {
#vgroup->rgroup
vgroup_mapping.zhaoxingban-member-fescar-service-group = "default"
#only support single node
default.grouplist = "127.0.0.1:8091"
#degrade current not support
enableDegrade = false
disable = false
max.commit.retry.timeout = "-1"
max.rollback.retry.timeout = "-1"
}

When the server runs locally, executing ./seata-server.sh connects successfully regardless of the IP in the configuration. On a cloud server the same command fails because the cloud environment cannot reach the configured address. Adding the external IP and port to the startup command resolves the issue: ./seata-server.sh -h <external_ip> -p 8091 & After using the corrected command the connection errors disappear.

Some services may leave a Seata daemon process running even after the main process is killed. To verify, run ps -ef|grep seata; the screenshot below shows the lingering process, which can then be terminated with kill.