nfs problem

[Ding Honghui <hhding.gnu@gmail.com>]

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nfs server 192.168.110.28
Filesystem            Size  Used Avail Use% Mounted on
/dev/sdb1             2.2T  1.6T  473G  78% /home

/etc/exports
/home/nfs_for_217  192.168.110.27/255.255.255.255 (rw,sync,no_root_squash)

nfs client
Filesystem            Size  Used Avail Use% Mounted on
192.168.110.28:/home/nfs_for_217
                      170G -417G  474G   -  /data_nfs218

What's the problem? The field Used is -417 and field Use% is -.
It's really strange..

thanks

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