Unable to access the configuration object : REST API failure, code : 500

I try to start gwcli after adding two iSCSI VM to a running cluster. With the first install it was working up to the point where I started adding the gateways. The command was hanging and I had to kill it. Since then I get the above error when starting gwcli

[root@duscephiscsi1 ceph]# gwcli -d
Adding ceph cluster 'ceph' to the UI
Fetching ceph osd information
Querying ceph for state information
**Unable to access the configuration object : REST API failure, code : 500
GatewayError:**
Traceback (most recent call last):
File "/usr/bin/gwcli", line 194, in
main()
File "/usr/bin/gwcli", line 105, in main
root_node.refresh()
File "/usr/lib/python3.6/site-packages/gwcli/gateway.py", line 84, in refresh
raise GatewayError
gwcli.utils.GatewayError

tcmu, rbd-target-* process are all running on all hosts. Nothing in log files for tcmu, rbd-target-* or messages. Using RHEL 8.2 with RH Ceph Storage 4.1.

Appreciate your help. Thanks.

Start by reproducing the failure with `gwcli -d` in the reported RHEL 8.2 and RH Ceph Storage 4.1 setup. Inspect `/usr/bin/gwcli`, especially `main` and `root_node.refresh()`, and `gwcli/gateway.py` around line 84, then trace the REST API 500 response; done means gwcli starts without the configuration-object error.

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