IPv6 support for NFS?

[KNBu5ZMdbR]

Is there any OS support out there for NFS over IPv6?  I've checked SusE Linux, RHEL, Ubuntu and Windows and none of them do, from what I can tell.  My test is to start the NFS server and run "netstat -a".  I see a process listening for the nfs service over TCP and UDP on IPv4, but not in IPv6.  I also have tested via telnet.  Telnet will connect over an IPv4 address but not IPv6.

VMWare ESX supports IPv6 addresses for its VMK interfaces so, presumably, it could mount IPv6 NFS data stores -- if I could find anyone to serve them.

[jimb]

Hrm.  I'm really not sure about this.  NFS would require not only an nfsd that'd support it, but all the other little pieces that go with it, like a Sun RPC that supports it, RPC portmapper which supports it, and all the little RPC daemons that go along with NFS for various functions.

[broquea]

Thought NFS 4 with solaris/opensolaris was ipv6 happy.

[jimb]

Thought NFS 4 with solaris/opensolaris was ipv6 happy.

I wouldn't know.  I haven't messed with solaris, or really, NFS, for years.  

EDIT: I just checked and at least on gentoo linux, the netkit portmap daemon doesn't appear do IPv6.  Neither does the one in Ubuntu linux 9.10.  Not sure about other distros, or the *BSDs.  So the only choice may be Solaris, although if Solaris has it, the *BSDs might too.

[cholzhauer]

Telnet will connect over an IPv4 address but not IPv6.

That depends on your OS.  In FreeBSD, Telnet listens on both IPv6 and IPv4

Code:

mars# netstat -a
Active Internet connections (including servers)
Proto Recv-Q Send-Q  Local Address          Foreign Address       (state)
tcp6       0      0 *.telnet               *.*                    LISTEN
tcp4       0      0 *.telnet               *.*                    LISTEN

I can connect via IPv6 too

Code:

[carl@mars ~]$ netstat -a
Active Internet connections (including servers)
Proto Recv-Q Send-Q  Local Address          Foreign Address       (state)
tcp6       0      2 mars.telnet            cholzhauer.59857       ESTABLISHED

EDIT:

I talked to a guy here that uses Solaris quite a bit.  He's 97% sure that NFS for Solaris supports IPv6; what he's not sure about is the GUI settings for NFS supporting IPv6

[KNBu5ZMdbR]

That depends on your OS.  In FreeBSD, Telnet listens on both IPv6 and IPv4

I was speaking in terms of the nfs port.  Telnet to port 2049 (nfsd) over IPv4 connects, telnet to port 2049, IPv6, does not.  That's a simple test I use to see if a program allows connections over TCP/IP.

$ telnet localhost 2049
Trying 127.0.0.1...
Connected to localhost.localdomain (127.0.0.1).
Escape character is '^]'.
^]
telnet> quit
Connection closed.
$ telnet localhost6 2049
telnet: connect to address ::1: Connection refused
telnet: Unable to connect to remote host: Connection refused
$

[KNBu5ZMdbR]

FYI.  Here's a follow up.

RHEL 6 can serve NFS over IPv6.  An RHEL6 client can mount a file system exported by an RHEL6 server and you can see that IPv6 is used by looking at netstat.

Also, vmWare v4 can mount NFS over IPv6.  I created a VMkernel port with just an IPv6 address, and added a datastore.  Netstat shows that vmWare is getting the datastore through IPv6 from my RHEL 6.1 server.

Really cool!

[charleslacour]

Support for IPv6 in some the linux daemons has been there a while but one of the slowest adopters is NFS. 

The easiest way to see if your Linux server/system that hosts your NFS exports is to use the command "lsof -i".  You will likely have to run the command as root to get all of the info.

You will want to look for the "portmap", "rpc.rquota", "rpc.statd" and "rpc.mount" processes and the type of interface.  If they all have both IPv4 and IPv6 you are good to go.

For the most part if the system supports NFSv4 you have a good possibility of having IPv6 support but if it is NFSv3 it is very unlikely.