[vox-tech] NFS Mounting Error

[Chris Jenks]

On Sat, 4 Dec 2004, Peter Jay Salzman wrote:

> On Sat 04 Dec 04, 10:44 AM, Chris Jenks <jenks at resonance.org> said:
>>
>>   Hello,
>>
>>   I am trying to mount a NFS volume where both machines are on the same
>> home network, but I get the following errors. From the client:
>>
>> [root at pinky mnt]# mount -t nfs 192.168.0.14:/tmp /mnt/tmp
>> mount: 192.168.0.14:/tmp failed, reason given by server: Permission denied
>>
>> On the server:
>>
>> cruncher:/# tail /var/log/syslog
>> [...]
>> Dec  4 10:30:31 cruncher rpc.mountd: authenticated mount request from
>> 192.168.0.2:773 for /tmp (/tmp)
>> Dec  4 10:30:31 cruncher rpc.mountd: getfh failed: No such device
[...]
>
> Chris, if massive log file reading and Googling didn't turn up anything
> useful, what I would try as a second stab would be to run nfsd by hand with
> strace:
>
> # strace -o /root/nfsd.log rpc.nfsd
>
> and look for something that looks like an error near the bottom of the file.
> It may not tell you anything useful, but often time strace will tell you the
> real, "low level" reason why something failed, which can sometimes be very
> useful.
>
> Pete

   Dear Pete,

   Thanks for the new tool. I tried it out on rpc.nfsd and it gave:

[...]
close(5)                                = -1 EBADF (Bad file descriptor)
close(4)                                = -1 EBADF (Bad file descriptor)
close(3)                                = 0
open("/proc/fs/nfsd/threads", O_WRONLY) = -1 ENOENT (No such file or directory)
open("/proc/fs/nfs/threads", O_WRONLY)  = -1 ENOENT (No such file or directory)
nfsservctl(0, 0xbffff4c0, 0)            = -1 ENODEV (No such device)
time([1102190507])                      = 1102190507
open("/etc/localtime", O_RDONLY)        = 3
[...]

near the end. Also, I ran exportfs -ra in the same way, and got:

[...]
open("/var/lib/nfs/xtab", O_RDONLY)     = 5
fstat64(5, {st_mode=S_IFREG|0644, st_size=0, ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x40018000
read(5, "", 4096)                       = 0
read(5, "", 4096)                       = 0
close(5)                                = 0
munmap(0x40018000, 4096)                = 0
close(3)                                = 0
nfsservctl(0x1, 0xbfffe7f0, 0)          = -1 ENODEV (No such device)
write(2, "192.168.0.2:/tmp: No such device"..., 33) = 33
open("/var/lib/nfs/etab", O_RDWR|O_CREAT, 010000510074) = 3
rt_sigaction(SIGALRM, {0x804dec0, [], 0}, {SIG_DFL}, 8) = 0
[...]

A google search revealed that nfsservctl is a "syscall interface to kernel 
nfs daemon." Command number 0 means "This is a server process," while 
command number 0x1 means "Add an NFS client." I suspect that my kernel 
configuration is at fault. I'll look at it.

   Yours,

     Chris