Home > Storage > Unity XT > Virtualization, Cloud & Applications > Dell Unity XT: Oracle Database Best Practices > dNFS and network verification checks
This section discusses the following topics:
To verify that the database instance is using dNFS, check the database alert log for the string running with ODM. If the string is found, as shown in Figure 64, the instance was started with the ODM library containing the direct NFS driver:
The database compares the datafile names with the NFS mount to see if the datafiles can be used by dNFS. Any datafile that dNFS has open resides in v$dnfs_files. To verify that dNFS has opened files residing on the NFS share, run the following SQL*Plus command:
Note: Only database files that dNFS has open will be displayed in v$dnfs_files.
To verify the correct network endpoints are being used with dNFS, look for the string Direct NFS: channel id in the database alert log. The path and local IP addresses shown in the alert log should match all the local:path mappings in file oranfstab for the appropriate NAS server hosting the database.
If Oracle automatically detects the local host interface because oranfstab is not defined, ensure that the chosen interface is intended to be used for the dNFS channel.
Figure 66 shows that the database instance created a dNFS channel for each local:path mapping specified in oranfstab:
If the operating system network routes are set up correctly for dNFS, a traceroute from the database server can reach the NAS network interface in Unity. Also, netstat should report increasing TX/RX metrics on the interfaces intended for dNFS during database activity.
If dNFS is enabled but oranfstab is not configured, the Ethernet traffic for dNFS will reside on the interface used to mount the NAS share.
With or without oranfstab, dNFS activity will be displayed as changes to RX-OK and TX-OK values from netstat.
Figure 67 shows two hops between the endpoints in the routes:
Figure 68 shows netstat send/receive (TX/RX) statistics for the database server Ethernet interfaces. The statistics can be monitored during database activity to ensure that the interfaces for dNFS traffic have TX/RX activity.
eno3 is the public Ethernet interface. Low values of RX and TX for eno3 are a good indication that the public Ethernet interface is not used by dNFS.
Note: The netstat statistics are counters that are only reset with a system boot.
The following SQL*Plus output shows dNFS send/receive (TX/RX) statistics for each dNFS channel. If dNFS is correctly configured, all channels appear in the output, and have read and write activity.