[SOLVED] Debugging NAS connection!

[blnl]

Recently I attached Sitecom MD-250 NAS unit to my wireless modem/router. I can mount my NAS in different ways (all give me access to my files):

mount //10.0.0.171/public /windows/NAS –o nolinux
mount.cifs //10.0.0.171/public /windows/NAS –o nolinux
mount –t cifs //10.0.0.171/public /windows/NAS –o nolinux

The problem is that my system frequently hangs when I’m performing operations on NAS, leaving me with a frozen desktop. No response from the keyboard/mouse. Only two led’s (caps-lock and scroll-lock) on the keyboard are flashing.
This problem is triggered by performing one of the following operations on the NAS:

du –sh .
ls –lR DirName
rm –R DirName

However, performing these operations on a single file does not result in system freeze.
This problem can be reproduced on both Linux machines (see the signature).

Can someone help me debug this issue?

Maybe an additional option is required in the mount command?
Or, should I install some patches, and which?

Boris
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openSUSE 11.0, GNOME
HP Compaq NC6000, Intel Pentium M Processor 725, ATI Mobility Radeon 9600, Intel PRO 2200BG
HP Compaq ND7100, Intel Pentium 4 Processor 521, Intel 915G Express, D-Link DWL-510 AirPlus G

[Rubberman]

This sounds like a problem with the cifs file system driver. Even if there is a CIFS implementation problem on the NAS it shouldn't cause a client system to behave like this. Have you checked on the openSUSE web site forums for anyone else with similar problems? FWIW, I have 2 Buffalo TeraStation NAS's on my network and I have never experienced this sort of problem with my client systems (CentOS/RHEL 5, Windows XP, Windows XP VM, Solaris x86 VM).

[blnl]

I have asked the same question on openSUSE forum, but nobody replied yet.
This problem is very frustrating because I just bought this NAS, which appears to be completely useless. However, I can't return it to the shop until I can prove that NAS is not functioning properly. Since the NAS functions properly with Windows, I have a difficult case.

Is there a way to debug these kind of problems and determine what is the root cause, or am I just screwed?
In other words, I can start replacing my equipment, starting from NAS, wireless router, wireless adapter, etc. I can spend a fortune on it, and still there is no guarantee that the other equipment will work properly.

[Rubberman]

You could run a network sniffer and see if there are any weirdnesses with the packets sent/received between the system and NAS, but you would need to know a lot about the internals of the Samba/CIFS protocol to tell what's going wonky. Personally, I don't have that knowledge base so this is about as good as you are going to get from me. Sorry.

[blnl]

Thanks Rubberman!
I'll try to see if I can connect my NAS directly to the PC (without wireless router in between). If the problem can be reproduced, at least I'll know that it is not due to my wireless configuration/hardware.

In the meantime, anyone who knows how to address this issue, please reply.

[Rubberman]

I didn't realize you were using wireless to connect with the NAS, though I see you mention the wireless devices you have with your systems. Connecting via hard wire to the router/nas would be a good thing to test. It's possible that there is some interference going on with the wireless connection that is affecting you. Just to know, but what security protocols do you use for your wap? Is it wep, wpa, or none?

[blnl]

Yes, indeed my NAS is attached to a wireless modem. Modem has a DHCP server, and NAS has a fixed IP address. I'm using WEP security protocol.

[blnl]

I'm trying to establish wired network connection with my NAS, but unsuccessfully. I.e. I have no clue what I'm doing.

For example ifconfig eth0 gives the following output:

eth0      Link encap:Ethernet  HWaddr 00:11:85:83:3A:12  
          inet6 addr: fe80::211:85ff:fe83:3a12/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:240 errors:0 dropped:0 overruns:0 frame:0
          TX packets:30 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:60996 (59.5 Kb)  TX bytes:2028 (1.9 Kb)
          Interrupt:11

It seems as some bytes are transfered over the network. However there is no way to mount or detect NAS on the other side of the cable.
I have tried ping, mount, firefox. Nothing seems to detect NAS.

I'm completely stuck here!

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By the way in Windows XP (on the same machine) NAS is instantly accessible. ipconfig /all gives the following details:

Windows IP Configuration
Host Name . . . . . . . . . . . . : notebook
Primary Dns Sufix . . . . . . . . :
Node Type . . . . . . . . . . . . : Unknown
IP Routing Enabled. . . . . . . . : Yes
WINS Proxy Enabled. . . . . . . . : No
Ethernet adapter Local Area Connection:
Connection-specific DNS Suffix  . :
Description . . . . . . . . . . . : Broadcom NetXtreme Gigabit Ethernet
Physical Address. . . . . . . . . : 00-11-85-83-3A-12
Dhcp Enabled. . . . . . . . . . . : No
IP Address. . . . . . . . . . . . : 192.168.0.1
Subnet Mask . . . . . . . . . . . : 255.255.255.0
Default Gateway . . . . . . . . . :

In the NAS web interface I see following details:

Network Information  
IP Address      192.168.0.132  
DHCP Server     Off

[blnl]

When I contacted Sitecom helpdesk about this issue, they replied "unfortunately we do not support Linux on our devices."

I have returned the product, and now I'm considering buying one of these (which do support Linux):

• QNAP NAS Server TS-109
• Synology NAS Server DS109

Therefore, I consider this problem solved!

Lessons learned:
Never buy cheap stuff, it really does not work.