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Our upstream provider assigned us a single /32 ip address. How can we configure our FreeBSd server to use it?

So far we have this in /etc/rc.conf:

ifconfig_em0="inet a.b.c.d/32 netmask"

But when we attempt pings it says no route to host. What are we missing?

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Did they assign you a /32 that is already routed on an Ethernet network with some other netmask? Or are they just routing a /32 to you and the machine already has an IP address? In what sense is that IP address associated with a particular physical Ethernet interface? You need to understand how this is supposed to work to configure it correctly. There are multiple possibilities. (A /32 primary makes no sense for Ethernet. What other machine could you ever talk to? No other IP would be on that network.) – David Schwartz May 14 '14 at 6:32
We are assigning this to a virtual machine. We have 1 other IP that is a a.b.c.d/26. They stated our other IP's are /32's and we should use the subnet mask They also said "There is no gateway they are /32's. You have to route them back via your host interface." – techfutures May 14 '14 at 6:40
Are you bridging to the VM or routing to it? – David Schwartz May 14 '14 at 7:13

If you are bridging to the VM, assign it a.b.c.d/26 and don't assign it subnet mask If you are routing to the VM, assign a.b.c.d/32 as an alias to the loopback interface and route a.b.c.d to its (unrelated, can be private) ethernet address.

Their comments seem to suggest you should be routing these IPs to your VMs. So assign these IPs as aliases to the loopback interfaces (since they aren't associated with any particular physical interface) and route them to them.

If you don't understand how to route an IP address to a machine, then you're out of your depth and should employ someone who does to work with your provider to get the configuration right.

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