Problem with directory listing of nfs filesystem

[luckyrings]

I have problem with NFS file systems which have been mounted on my client computer with Ubuntu 12.04.4 LTS. The server is a non Ubuntu distribution (TeraStation TS-WXL / FW 1.63).

After mounting the exported file system on my Ubuntu and doing a directory listing, the listing is not possible.

It shows only Input/Output error.

Everything else like addressing single file (with rm, cp....) or changing directory command works fine. I found out that the error appears only when a certain amount of files together with certain file name length has been stored in the affected folder.

Here some example output when the error appears. The user / server / path has been anonymized.

user@server:/media/example/test$ ls
100000000000000000000000000000000000 19999999999999999999999 6666666666666666666666666666666666 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
1111111111111111111111111 200000000000000000000000000000 777777777777777777777777777777 file2
111111111111111111111111111111111118 210000000000000000000000000000 888888888888888888888888 long filename filname 0223123131.121321
11111111111111111111111112 220000000000000000000000000000 999999999999999999999999
1111111111111111111111111333 2300000000000000000000000000000000000 99999999999999999999999999999999999
11111111111111111111111144444 6666666666666666666 aaaaaaaaaaaaaaaaaaaaaaaaaaaaa
user@server:/media/example/test$ touch file34
user@server:/media/example/test$ ls
ls: reading directory .: Input/output error
user@server:/media/example/test$ rm "long filename filname 0223123131.121321"
user@server:/media/example/test$ ls
100000000000000000000000000000000000 11111111111111111111111144444 2300000000000000000000000000000000000 999999999999999999999999 file34
1111111111111111111111111 19999999999999999999999 6666666666666666666 99999999999999999999999999999999999
111111111111111111111111111111111118 200000000000000000000000000000 6666666666666666666666666666666666 aaaaaaaaaaaaaaaaaaaaaaaaaaaaa
11111111111111111111111112 210000000000000000000000000000 777777777777777777777777777777 bbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbbb
1111111111111111111111111333 220000000000000000000000000000 888888888888888888888888 file2
user@server:/media/example/test$ touch file35
user@server:/media/example/test$ ls
ls: reading directory .: Input/output error
user@server:/media/example/test$

[luckyrings (d8f2)]

Concering to RPC Info and Wireshark investigation version 3 is used by the server:

user@server /var/log $ rpcinfo -s terastation | grep nfs
    100003 3 tcp,udp nfs unknown

Question is if it is client problem, or not.