Networking: Which port for networked GB Router and Switch?

[DoeBoye]

Hey folks,

 

I've been running without problems a network with the following configuration:

 

MODEM -> GB ROUTER -> UNMANAGED GB SWITCH -> PCs etc and UnRaid Box

 

So the question I have been musing about is the following:

 

Would transfers between my UnRaid server and the other computers on the network be faster if the UnRaid server was plugged into one of the ports of the router instead of the switch?

 

ie:

MODEM -> ROUTER -> SWITCH -> PCs
                -> UnRaid Box

 

My reasoning is that if all the computers are plugged into the switch, and the switch is plugged into one port on the router, perhaps all traffic needs to pass through that one port before being sent to the correct target on the switch...

 

Of course, I find it entirely likely that the packets being sent never actually leave the switch at all and just travel from one port to the other... in which case plugging the unraid box directly into the router would only complicate things and potentially reduce transfer speeds slightly...

 

So again, I have no actual problems, just hoping to squeeze every last MB of speed out of any file transfers over the network!

 

Anyone with a more thorough knowledge of the topic willing to share some insight?

 

Cheers,

 

DB

[Chris Pollard]

 

Of course, I find it entirely likely that the packets being sent never actually leave the switch at all and just travel from one port to the other... in which case plugging the unraid box directly into the router would only complicate things and potentially reduce transfer speeds slightly...

 

 

This should be the case.  What transfer speeds are you getting?

[DoeBoye]

This should be the case.   What transfer speeds are you getting?

 

Thanks for the quick reply!

 

Transfer speeds are usually around 30 - 40 MBps (Using cache drive) from PC to UnRaid. Also, when tested using an SSD drive as the source, these numbers did go up to closer to 50 MBps, so obviously the source drive is definitely a bottleneck here... Though you would think the read speeds on the platter drive would be better then that...

 

So, though not the fastest transfers in the UnRaid world, from what I've seen, I am within the normal range... I guess I'm just being extra greedy

 

 

[Spectrum]

Keep it the way you have it.  As is the only traffic that will go up to the router is traffic destined for the Internet, all system to system traffic will be handled by the switch.  That said, unless the switch or the router is a real POS you probably wouldn't notice any real world difference.

 

If you want to test raw bandwidth, you can use something like Iperf to get an idea what your network is capable of.

[Chris Pollard]

Yep, seems pretty normal.  Maybe worth checking your switch doesn't have any port contention, but even if it does, re-arranging the deck chairs ports will not help, you will have to replace the switch to get better performance.

[DoeBoye]

Keep it the way you have it.  As is the only traffic that will go up to the router is traffic destined for the Internet, all system to system traffic will be handled by the switch.  That said, unless the switch or the router is a real POS you probably wouldn't notice any real world difference.

 

Thanks Spectrum! I believe I will keep things as is. For the record, the Switch is an 8 port HP ProCurve, and the router is an Asus RT-N16 running TomatoUSB... I believe both are considered to be pretty solid so replacing them won't help... I may invest in a new platter drive for my Windows box and see if that makes a difference (Seeing as it speeds up when copying from the SSD drive). The existing data drive on the PC is an old PATA drive.

 

Yep, seems pretty normal.  Maybe worth checking your switch doesn't have any port contention, but even if it does, re-arranging the deck chairs ports will not help, you will have to replace the switch to get better performance.

 

Funny story : I googled "Port Contention" to make sure I understood what was going on, and I skimmed the first few posts in one of the first links I clicked on, before I realized it was a discussion on Sea Ports in some Online Pirate game! *Grin*.

 

So, as per a few lines up, unless my hardware is faulty, I doubt replacing either switch or router will improve speeds... To be honest, I've been very pleased with the performance of both units. They never go down, never heat up, and seem to just work without any intervention.

 

I think this is just me being anal a perfectionist  . Thanks for the advice though!

[jeff.lebowski]

I posted this a while back on another networking thread, and I really liked it, so here it is again:

 

When transferring files among devices on the network, they communicate only among the switch's ports with the faster of the two speeds, gigabit. But when the devices need to go outside the house, they use the router.

 

Think of a 400m track used for sporting events. The inside lanes (gigabit switch) are on the same track as the outside lanes (router), yet arrive at the finish line sooner by avoiding those slower outside lanes.

 

[DoeBoye]

Great analogy! Thanks!

 

[abq-pete]

 

Transfer speeds are usually around 30 - 40 MBps (Using cache drive) from PC to UnRaid. Also, when tested using an SSD drive as the source, these numbers did go up to closer to 50 MBps, so obviously the source drive is definitely a bottleneck here... Though you would think the read speeds on the platter drive would be better then that...

 

So, though not the fastest transfers in the UnRaid world, from what I've seen, I am within the normal range... I guess I'm just being extra greedy

 

 

I would also check your cache drive.  Transfers from my PC to the cache drive are usually around 75MB/s (ranges from a high of 95 to a low of 55).  This is between two 7200rpm drives over a gigabit (unmanaged) switch.

 

Regards,  Peter

[DoeBoye]

I would also check your cache drive.  Transfers from my PC to the cache drive are usually around 75MB/s (ranges from a high of 95 to a low of 55).  This is between two 7200rpm drives over a gigabit (unmanaged) switch.

 

Regards,  Peter

 

75MB /s? I've never seen anything near that!

 

My cache drive is a WD EARS drive. I considered getting a faster cache drive, but I like the idea of having it as a warm spare and I'm trying to stick with green drives... Maybe when I get my new case (norco 4224), I'll pick up a WD Black at the same time and have an extra green drive in an empty slot...

[Velkitor]

I would also check your cache drive.  Transfers from my PC to the cache drive are usually around 75MB/s (ranges from a high of 95 to a low of 55).  This is between two 7200rpm drives over a gigabit (unmanaged) switch.

 

Regards,  Peter

 

75MB /s? I've never seen anything near that!

 

My cache drive is a WD EARS drive. I considered getting a faster cache drive, but I like the idea of having it as a warm spare and I'm trying to stick with green drives... Maybe when I get my new case (norco 4224), I'll pick up a WD Black at the same time and have an extra green drive in an empty slot...

 

You don't need a 2tb cache drive.  If you use a PC when you upgrade your desktop next take the 7200rpm drive out of there.  Bam instant cache drive.

I am not afraid of my cache drive dieing,  I backup the .custom folder periodically so if it does die due to being an older performance drive big deal.  I have SAB/Sickbeard, and Sickbeard moves completed items to the user share when they are done downloading (few more spin-ups than waiting for the mover but they are safe)  My mover runs 4 times a day to keep things in check (it does this b/c the cache drive is an old 7200rp 120gb HD.)

 

 

[DoeBoye]

You don't need a 2tb cache drive.  If you use a PC when you upgrade your desktop next take the 7200rpm drive out of there.  Bam instant cache drive.

I am not afraid of my cache drive dieing,  I backup the .custom folder periodically so if it does die due to being an older performance drive big deal.  I have SAB/Sickbeard, and Sickbeard moves completed items to the user share when they are done downloading (few more spin-ups than waiting for the mover but they are safe)  My mover runs 4 times a day to keep things in check (it does this b/c the cache drive is an old 7200rp 120gb HD.)

 

I used to use an old 400GB sata drive as my cache drive until I read about Rajahal's "Warm Spare" concept of using a precleared cache drive the same size as your largest drive.

 

In the event that one of your other array drives fails, it's just a matter of clearing off the content from the cache drive, unassigning it as cache, and reassigning it in the failed drive's slot. Once the array rebuilds the failed drive's data on the ex-cache drive, your array is back and fully protected (minus a cache drive of course).

 

Here's some more info on it: http://lime-technology.com/forum/index.php?topic=5754.0

 

Just gives me a bit more sense of security I suppose ...

 

That said, I may purchase a faster drive for cache, and in the event an array drive fails, I could do the swap, and simply swap it back to cache when a new green drive has precleared and is ready to go....

 

Eventually, once I have a larger case, I will simply keep the faster drive in the cache position, and have an unassigned precleared green drive as a spare waiting in an extra slot...