lan or wan ?

Unanswered Question
Jun 16th, 2008

Hi to all.Maybe someone can suggest me the tunning to do for my problem.

I have 2 cisco routers with a 10Mb/s-full duplex WAN connection each.If I do an FTP between from a PC on site 1 to a pc on site 2 I reach 9.8Mb/s.Great!!!!

If I transfer the same file using a simple Microsoft Copy/Paste I'm not able to do a better transfer than 4Mb/s.

What I've done:

1)Put all may LAN-switch interfaces to full-duplex 100.

2)Set all the possible MTU's to 1500.

3)Did some traffic shaping on the wan link to smoothen out the bottle neck:

policy-map 3111-RM2

class class-default

bandwidth 1000

policy-map 3111-RM2-OUT

class class-default

shape average 10000000

service-policy 3111-RM2

interface GigabitEthernet4/1/0.897

service-policy output 3111-RM2-OUT

With all these things I managed to get a speed (with copy/paste) of 6Mb/s.

Does anyone have any suggestions on what else I can do or maybe missing?Is it correct that I loose that much speed if I don't use FTP? Do you think I might be albe to do better if I use some tcp adjust-mms (about 1452) on my routers?

I have this problem too.
0 votes
  • 1
  • 2
  • 3
  • 4
  • 5
Overall Rating: 0 (0 ratings)
Loading.
Joseph W. Doherty Mon, 06/16/2008 - 03:38

You shouldn't obtain any advantage to using a reduced MSS unless your Ethernet is using something like PPoE.

My guess would for the difference in performance between the FTP and copy/paste has to do with SMB not being quite as efficient as native TCP. You might check whether your doing the copy/paste with SMB directly over TCP (port 445) or whether your doing SMB over NetBT (port 139). If the latter, try the former and see if it increases transfer performance.

With regard to your policy, the shaper only makes sense if your 10 Mbps WAN has 100 Mbps LAN handoffs. If possible, eliminate the shaper by setting the LAN handoff interfaces to 10 Mbps. If the shaper is eliminated such that a 10 Mbps interface is being used, eliminate the child policy and set the existing parent's class-default to fair-queue.

Also, with you policy, if you retain the shaper, suggest you either eliminate the child policy or use fair-queue with the child's class-default.

freccetta Mon, 06/16/2008 - 04:37

I'll check if the SMB is done over NetBiois. yes my LAN interfaces are Fast 100Bps .So i guess the policy makes sense .

I'll see if i can put the lan fast setting to 10Mbps.

"eliminate the child policy and set the existing parent's class-default to fair-queue."

At this point can't I just take out the policy and make the fastethernet do fair-queing?

Joseph W. Doherty Mon, 06/16/2008 - 06:48

"At this point can't I just take out the policy and make the fastethernet do fair-queing?"

Assuming you run the physical interface at 10 Mbps, you'll no longer need the shaper, but interface fair-queue doesn't seem to scale well with fast interfaces like Ethernet. Fair-queue within a CBWFQ class-default class, does seem to scale. In theory, since class-default is always present even when not explicitly defined, and I believe FQ within the class is also the default, something as simple as:

policy-map x

interface fastEthernet #

service-policy output x

might be enough.

freccetta Mon, 06/16/2008 - 07:07

Ok so I can take out the child.I have done some investigation upon SMB and from what I have read it seems that it's possible to have a on file transfer reduce up to 40% than FTP.Of course FTP is the right way to go but I'd never immagine that much diff.

Actions

This Discussion