Gigabit Switch Blue.....

[hkkelvinlee]

I got a strange problem. Not sure if it is real or I am just chasing ghost.

I have a simple home network. ADSL modem connected to my wireles router (Linksys WRV200, not giga speed). I also have a PC (Asus P5Q Deluxe) and NAS (Synology DS207, firmware 2.2-942), both with gigabit LAN. I do a lot of media (mainly photos in RAW format) upload and download between PC and NAS. Since they are both giga speed and router is not, I did the only logical thing by buying a small 5 ports dumb giga switch (Level One GSW0507 H/W 2.0). I connect both PC and NAS to switch by Cat 6. Then a Cat 5e between switch and router. I have a samba (via Windows explorer) transfer from NAS to PC at 20 to 30 MB/s. Not great but decent for little money I spent.

Then I bought an IP cam (Panasonic BB-HCM511). It is not giga speed. I am not aware of any ip cam that is anyway. I plugged that into the switch by Cat 5e, and enable NAS' "Surveillance Station" function so that the NAS box will review the video stream (on 24/7 basis) from the ip cam and do motion detection/recording.

Then I got a problem. My samba speed between PC and NAS dropped to little over 10 MB/s. When I unplugg the ip cam Cat 5e, the speed shoot back up to >20 MB/s.

I believe the switch is not powerful enough to handle the traffic. If changing a switch can help, I am happy. However, the video stream from ip cam is like 400KB/s only accordingly to the Resource Monitor in the NAS box.

NAS' CPU and RAM should not be a problem. CPU usage is never >70%, and RAM never >40-50%. I am not sure about hard drives and LAN I/O in the NAS though but the fact that it can do up to 30MB without the ip cam plugged in shows the I/O cannot be the issue.

Why is that? Can swapping a SMB switch (like Netgear GS108) or even a managed switch help? I am not asking like 70MB/s as I know the limit of NAS box but I really want about 30MB/s back.

Many thanks for your guidance.

Cheers,
Kelvin

PS. By the way, I swap in a D-Link DGS-1008D and the result ensured. The D-Link has lights indicating speed of switch ports. Those connected to PC and NAS do not drop from giga to 100 upon pluging in of ip cam.

 

[thiggins]

What happens if you disable the NAS Surveillance Station function, but leave the camera plugged in?

And what happens if you move the IP camera from the Gigabit switch to the router's switch?

 

[hkkelvinlee]

Thanks for the feedback. Much appreciated. Answers below:-

What happens if you disable the NAS Surveillance Station function, but leave the camera plugged in?

And what happens if you move the IP camera from the Gigabit switch to the router's switch?

1. It goes back to normal with samba speed between 20-30MB/s. No more video stream pulling from ip cam to NAS through the switch. The blinking of the two lights for ports linked to NAS and ip cam slowed down dramatically. When surveillance was enabled, the two lights blink like crazy. So quickly that they almost appear constantly lit.

2.No change at all. Samba transfer still limited to about 10MB/s. I reckon the video stream is routed from router back to switch and then NAS. Going through the switch all the same.

Any insight? Many thanks again.

Kelvin

 

[thiggins]

When surveillance was enabled, the two lights blink like crazy. So quickly that they almost appear constantly lit.

There's your clue. Something in the camera or NAS setting is blasting traffic. The switch is probably fine. It's probably the NAS that is being overloaded. Check the Synology System Status for CPU and network usage.

 

[hkkelvinlee]

There's your clue. Something in the camera or NAS setting is blasting traffic. The switch is probably fine. It's probably the NAS that is being overloaded. Check the Synology System Status for CPU and network usage.

So I thought, Tim, but NAS CPU usage is always below 60-70% and network usage shows incoming traffic to NAS (the video stream) constantly at 400-500KB/s only. From these two indications, the NAS does not seem to have max'ed out......unless the NAS by design will significantly drop outgoing throughput (NAS to PC) with any substantive incoming (video stream) irrespective the latter's volume. Synology does not seem to publish whether the only giga port is full-duplex.

What say you? Thx.

Kelvin

 

[thiggins]

I'd be very surprised if the gigabit port is running only half duplex.
You don't have jumbo frames enabled on anything do you?

 

[hkkelvinlee]

I'd be very surprised if the gigabit port is running only half duplex.
You don't have jumbo frames enabled on anything do you?

Thanks, Tim. I have 9k enabled at NAS and PC and the switch supports that too.

I tried disable flow control at PC but makes no difference.

Kelvin

 

[thiggins]

I would doubt that jumbo frames are buying you anything. I'd disable them.

You would have to disable flow control at the NAS, since that is what is communicating with gigabit and 100 Mbps clients at the same time. But I don't think that you have that control. Guess you need a smart switch. When Flow Control is not a Good Thing

 

[hkkelvinlee]

I would doubt that jumbo frames are buying you anything. I'd disable them.

You would have to disable flow control at the NAS, since that is what is communicating with gigabit and 100 Mbps clients at the same time. But I don't think that you have that control. Guess you need a smart switch. When Flow Control is not a Good Thing

Thanks again. I have indeed read your article although I doubt if I understand all.

You are right the NAS has no setting to disable flow control. Will a smart switch (same thing as managed switch?) help? What about Netgear GS108T, which is readily available where I live? Other recommendation?

Thx again. It is a great site. Keep up the good work.

Kelvin

 

[thiggins]

Smart and managed are just different terms. GS108T should work, i.e. has per port flow-control disable.

 

[hkkelvinlee]

Smart and managed are just different terms. GS108T should work, i.e. has per port flow-control disable.

Hi Tim,

Just bought a HP ProCurve 1800-8G managed giga switch. It is being replaced by HP's 1810 series and hence price cut. Cheaper than Netgear GS108T in where I live.

Unfortunately, it does not help at all. I got stuck in the exact same problem with the dumb Level One and D-Link switches. The HP came with flow control disabled for all 8 ports. . I plugged them in, tried Jumbo Frame on and off and got little over 10MB/s. Tried enabling flow control in all ports but the one connected to NAS. Same result.

I am speechless.

KL

 

[thiggins]

Sorry that disabling flow control didn't help. I am out of ideas. Anyone else?

 

[MadKing]

For the panasonic camera, Have you try saving the files and video from different computer instead of the nas ? In my opinion, the NAS get overloaded by the streaming coming from the camera.


"2.No change at all. Samba transfer still limited to about 10MB/s. I reckon the video stream is routed from router back to switch and then NAS. Going through the switch all the same."

If you have an old hub somewhere or you Hp switch support port minnoring, you could check the traffic with wireshark (ethereal) between both device.

 

[hkkelvinlee]

For the panasonic camera, Have you try saving the files and video from different computer instead of the nas ? In my opinion, the NAS get overloaded by the streaming coming from the camera.


"2.No change at all. Samba transfer still limited to about 10MB/s. I reckon the video stream is routed from router back to switch and then NAS. Going through the switch all the same."

If you have an old hub somewhere or you Hp switch support port minnoring, you could check the traffic with wireshark (ethereal) between both device.

Thanks, MadKing, for your helpful input.

Have not tried using another PC to monitor the ip cam, so you could be right. But don't know why CPU, RAM and traffic flow usage as reported by NAS remain way below max'ed out.

I had no idea what Wireshark is so you know I am noob in every sense. Have since checked the web.

Given my passage that you quoted, I reckon you suggest me to plug ip cam Cat 5e into router, and router's cat 5e into a port at ProCurve 1800 switch ("source port"). The switch does support port mirroring. So I have traffic at source port mirrored at another port of the switch ("destination port") and run a cable from destination port to a spare PC (I have an Athlon XP 2500+ handy but only Fast Ethernet NIC ie.3Com 3C905C) which should run Wireshark.

Is the description about right? If not, any correction? Does Wireshark has Win GUI as opposed to commonand-line only?

If it is about right, I got a few silly questions:-

1.The source port (ie.cat 5e from router) contain not only ip cam video stream but all other internet traffic in the house. Will it distort any monitoring? Will it be better to plug ip cam cable directly into the switch and take that port (containing only ip cam traffic) or indeed the port connected to NAS as source port?

2.BTW, what am I supposed to look for whilst using Wireshark? Noob question indeed.

One thing that may help to explain my problem. When I look at network statistics logged by HP switch, it records 18 to 19 "receive error" for both ports running giga connected to NAS and PC whilst no error at ports to router and ip cam.

To Tim and MadKing both, a side question if you don't mind. Do you think HP ProCurve 1800-8G a better managed giga switch than Netgear GS108T? I aimed at buying GS108T but was talked out by salesperson because of bargin price of HP (being replaced by 1810 series, and was originally 30% more expensive than GS108T), and HP having a bigger name. Yeah, I am superficial. I know. I can still change for a GS108T if I wish. I have a Netgear FS108P POE switch powering the ip cam (plus connecting Wii, PS3 & Blue Ray player) at living room. Work like a charm, and completely cool to the touch. HP 1800 is slightly warm. If you say GS180T is better, faster & cool like my FS108P, I can switch the switch

Many thanks again.

Kelvin

 

[thiggins]

The ProCurves are well-regarded and some would say better than the NETGEAR. I wouldn't spend any more money on a smart/managed switch at this point, especially since it didn't solve your problem.

 

[MadKing]

You will need to connect directly the camera and the computer that will listen on the switch (not the router) at the port you have configured for port minoring.