Advice Please - CCTV Server Bandwidth

[charliesysadmin]

Hi all, I'm after some advice for our school CCTV server.  

 

Setup:

Hardware: Dell R510, 8gb ram (on average 4gb used), 12TB set to raid 1 storage (so we get great write speed), two gigabyte Nic's (only one is currently used to pull data from cameras)

Software: Windows Server 2012, Luxriot Evo S

Switches: Cisco 3750's

 

Problem:

The server and software works well and the ram, cpu doesn't seem to be straining under average load, but the video playback isn't as smooth as we'd like.  The past few months I've been eliminating possible bottlenecks, which had led to my concluding its a network bandwidth issue.  By my calculations, if I have 85 cameras feeding my server 4mb a second, I need at least 340mb of bandwidth.  I obviously can't get that with a single gigabyte connection (it seems to hit 200mb and not go any further, as that's a limit for gigabyte connection). 

 

So my plan is to activate the other nic and have dual gigabyte to help with the bandwidth load from all the cameras.  The problem is, I'm not sure the best way to go about this:

• Should I team up the ports on the Cisco switch?
• Or should I have half my cameras use 10.110.100.x and the other have use 10.110.101.x? 

What do you guys think?

 

Thanks for any advice you could give.

[Lurick]

You're confusing your bits and bytes as 8 bits = 1 byte. All data is transferred in bits and bandwidth is bits per second and switches support bandwidth in bits per second not bytes.

The MB/s limit for a 1Gb link is 125MB/s, not sure where the 200 limit is coming from.

If you're pushing 340MB/s (not Mb) of bandwidth then you'll need 3 1Gb links (125*3=375) to have enough bandwidth and you'll need to team three links together.

 

The problem is unless you're streaming really high bitrate and resolution you're only going to be sending 2 to 4 Mb/s not 4MB/s and that can easily be handled over a single gigabit link.

[charliesysadmin]

[BubblyCharizard]

the issue is more likely how you connected the secondary switches, that  can cause bottlenecks

[BubblyCharizard]

4 minutes ago, charliesysadmin said:

Thanks for your reply, do you think I should separate the cameras via IP range or configure the switch to team up the three gigabit ports?

 

Thanks for your advice.

I've attached a screenshot if it helps.

this is nowhere near saturated

[Lurick]

It would be easier to team a couple ports, just a couple lines of config to make it happen and it will load balance accordingly by source and destination IP so you'll get a half and half load balance across two links.

[charliesysadmin]

Thanks - I'll get reading.  From the screenshot, would you say that bandwidth looks like the issue? or am I going down the wrong path?

 

Thanks for your help.

[Lurick]

Just now, charliesysadmin said:

Thanks - I'll get reading.  From the screenshot, would you say that bandwidth looks like the issue? or am I going down the wrong path?

 

Thanks for your help.

What kind of disks are in the server, how many, and are they in RAID?

[charliesysadmin]

The OS disks are two raid 1 ssd's and then there are 4 sata disks at raid 0 and then 4 sas disks at raid 0.  I know raid 0 is risky, but I wanted to ensure that the HD's weren't the bottleneck.

[Lurick]

6 minutes ago, charliesysadmin said:

The OS disks are two raid 1 ssd's and then there are 4 sata disks at raid 0 and then 4 sas disks at raid 0.  I know raid 0 is risky, but I wanted to ensure that the HD's weren't the bottleneck.

Depending on the model, they could be the bottleneck. Search the model and it's rated throughput or write speed on google. I know the Cisco switches are line-rate switches so they don't have a problem pushing 1Gb/s of traffic per port in either direction.

[charliesysadmin]

SAS's have Negotiated speed of 6.00Gbps and RPM of 7200rpm (Model st200nm0023)

the SATA's have a Negotiated speed of 3.00Gbps and a RPM of 7200rpm (Model wd2003fyys

 

I've set the server up so that half the cameras write to the SAS raid, and the other half the SATA raid.  Both raids were setup via the hardware software and not windows etc.

[brwainer]

Is your issue with watching live video, or playing back recordings? In either case, please check:
-framerate that your cameras are configured at
-framerate that your software is requesting from the cameras
-framerate that your software actually gets from the cameras
-framerate of your recorded files, and do a frame-timing analysis of a few clips to determine if the framerate is steady, or if you have for example "15 fps" but there are 2 or 3 frames missing per second.