alertmanager: no private IP found

[Saeedeh Moghimi]

I made a service for alertmanager, which is like this:

Description=Alert Manager
Wants=network-online.target
After=network-online.target

[Service]
Type=simple
User=alertmanager
Group=alertmanager
ExecStart=/usr/local/bin/alertmanager \
  --config.file=/etc/alertmanager/alertmanager.yml \
  --storage.path=/data/alertmanager \ 
  --web.external-url http://public_ip_server:9093

Restart=always

[Install]
WantedBy=multi-user.target
 

I get this error when i start the alermanager
err="couldn't deduce an advertise address: no private IP found, explicit advertise addr not provided"

no private IP has been configed on this server, but I set --web.external-url http://public_ip_server:9093 , Why I still get this error?

[Saeedeh Moghimi]

It seems this label solve the problem
  --cluster.advertise-address="public-ip:9093"