Hello @秋山 泉
There is no simple solution to solve your problem, as unfortunately assigning static IP addresses to VPN clients with P2S VPN isn't currently supported.
Please see similar question. https://learn.microsoft.com/en-us/answers/questions/234465/azure-p2s-vpn-assign-static-ip.html
However there is a complex solution, that could help you to achieve your goal - "connect to the single onpremise server from a server on my Azure network with the same IP"
- Create a private DNS zone
mydomain.comon Azure and point it to your Azure virtual network with VM https://learn.microsoft.com/en-us/azure/dns/private-dns-getstarted-portal
- Create Task Scheduler on onpremise server( Running interval every 6 hours) to run a Powershell script that will Get VPN IP address and register A DNS name computer1.example.com in Azure Private DNS New-AzPrivateDnsRecordSet -Name computer1 -RecordType A -ZoneName mydomain.com -ResourceGroupName MyAzureResourceGroup -Ttl 3600 -PrivateDnsRecords (New-AzPrivateDnsRecordConfig -IPv4Address "Local VPN IP address"
- Azure VM will connect to on-premise computer using DNS name computer1.example.com