Here's a guide that might work: https://linuxconfig.org/configuring-virtual-network-interfaces-in-linux
I also found an alternative synology install method which might be helpful: Alternative Synology installation method
Here's a guide that might work: https://linuxconfig.org/configuring-virtual-network-interfaces-in-linux
I also found an alternative synology install method which might be helpful: Alternative Synology installation method