@vachagan_gratian 🙂
Yes that's a known bug, the workaround is to edit the JSON for the dashboard, in Grafana, and replace ${DS_GRAPHITE} by "default", I'm writing this from memory.
Be aware that in itself, this is not enough, you also need to enable the snapmirror plugin in harvest configuration (it's provided in standard distribution)
[EDIT]
Snapmirror extension is available in the extensions directory and enabled in the "template" directive of the config file, see IAG chapter 12
[my_controller]
hostname = 10.77.77.4
group = DEV
username = my_username
password = my_password
template = default, extensions.conf