Does ONTAP support 31-bit subnet masks for IPv4 point-to-point links?
Applies to
ONTAP 9
Answer
- ONTAP supports 31-bit subnet masks (/31)
- Only the second IP in the point-to-point range can be assigned to an interface in ONTAP
- TCP traffic to LIF's with a 31-bit subnet mask will not work until ONTAP 9.8
- ONTAP 9.8 introduces a fix for Bug 1326644 which will allow TCP traffic
-
Additional Information
Example
- Desired point-to-point subnet is 192.168.1.0/31
- ONTAP can be assigned 192.168.1.1
- ONTAP cannot be assigned 192.168.1.0
- Assignment will fail out with
Error: command failed: Netmask and address pair result in a network address
- Assignment will fail out with
- Below the first command fails, but the second command succeeds as stated above
cluster1::> network interface create -vserver svm1 -lif p2p -address 192.168.1.0 -netmask 255.255.255.254 Error: command failed: Netmask and address pair result in a network address cluster1::> network interface create -vserver svm1 -lif p2p -address 192.168.1.1 -netmask 255.255.255.254 cluster::>