While Oracle tech folks do their best to explain the meaning of not so many DNFS configuration file (oranfstab) parameters, I still find the official description a bit confusing. Therefore, I decided to share my understanding of the DNFS configuration parameters in hope that it will help someone or that if my understanding is wrong, someone corrects me :) So, if I am wrong please, please, please feel free to comment below.
Reasonably good description from Oracle folks
REF: Oracle® Grid Infrastructure Installation Guide 11g Release 2 (11.2) for Linux Part Number E22489-08
The parameters Enabling Direct NFS Client Oracle Disk Manager Control of NFS
- Server – Any name you want. This item has no technical impact whatsoever. This is kind of a configuration set’s alias used by instances to report the DNFS channels’ status or channel- related problems.
- “Local:” & “Path:” – Both parameters are IPs of a network card through which you want the DNFS traffic to be sent. “Local” is an IP on your database server. “Path” is an IP of a network card on the NFS server. You can configure up to 4 IPs for each parameter (assuming you have 4 different network cards).
- “Export:” & “Mount:” – This pair of parameters identifies a configuration set in an oranfstab file. You can have as many configuration sets as you want in a single configuration file. Each configuration set is relative to at least one or several pairs of mount points specified by an “Export”/”Mount” pair. “Export” parameter identifies a mount name on the NFS server, while “Mount” identifies the name of a mount point on a database server.
- Mnt_timeout: If an Oracle session doesn’t receive any response from a DNFS channel for the number of seconds specified by that parameter (default 10 mins), it drops the connection and marks the channel as unavailable. Comment: It sounds a bit too high for me.
- Dontroute: If specified, no OS TCP/IP routing process is used. The packages got sent to the network interfaces specified by “Local” parameter directly. It sounds logical to me.
oranfstab file example
server: nfs_data_cfg_set1 # Remember you can anything here. It doesn't have any tech meaning local: locIP1 # e.g. local:188.8.131.52 path: nfsIPa # this IP could be different from the one specified in a /etc/mtab local: locIP2 path: nfsIPb local: locIP3 path: nfsIPc local: locIP4 path: nfsIPd dontroute # Optional Mnt_timeout: 30 # Oprional export: /vol/orad1 mount: /ora_nfs_a export: /vol/orad2 mount: /ora_nfs_b export: /vol/orad3 mount: /ora_nfs_c # Note that this is where nfs_data_cfg_set1 section ends server: nfs_fra_cfg_set2 local: locIP5 path: nfsIPf local: locIP6 path: nfsIPg local: locIP3 path: nfsIPc local: locIP4 path: nfsIPd Mnt_timeout: 120 export: /u01 mount: /fra_nfs_a # this is where nfs_fra_cfg_set2 ends server: nfs_dpump_cfg_set2 .... export: /vol/interfaces mount: /d_pump_a # this is where nfs_dpump_cfg_set2 ends
Let me know if this post helped you or you found a mistake.