Managing routing in an SVM

The routing table for an SVM determines the network path the SVM uses to communicate with a destination. It’s important to understand how routing tables work so that you can prevent network problems before they occur.

Routing rules are as follows:

In the case of routes with the same destination, netmask, and metric, there is no guarantee that the system will use the same route after a reboot or after an upgrade. This is especially an issue if you have configured multiple default routes.

It is a best practice to configure one default route only for an SVM. To avoid disruption, you should ensure that the default route is able to reach any network address that is not reachable by a more specific route. For more information, see the Knowledgebase article.

SU134: Network access might be disrupted by incorrect routing configuration in clustered ONTAP

As part of a networking stack update for improved performance and resiliency, fast path routing support was removed in ONTAP 9.2 and later releases because it made it difficult to identify problems with improper routing tables. Therefore, it is no longer possible to set the following option in the nodeshell, and existing fast path configurations are disabled when upgrading to ONTAP 9.2 and later:

For more information, see Network traffic not sent or sent out of an unexpected interface after upgrade to 9.2 due to elimination of IP Fastpath.