Frustrating issue with 4 networked PCs

Liquid_Entity · 29 Nov 2016 at 22:32

Hi

I have a really strange problem with one of my support environments.

I have a DSL router coming in from outside world and a 5 port gb switch which then connects to the 4 PCs in the room. The PCs are all the same image but they are called Server, Client1, Client2, Client3. They are all imaged the same but commissioned with different computer names.

My issue is network transfer rates which is affecting the software installed on these PCs. The server contains the main software and database and then clients have the software installed but obtain the shared data from the database. It seems to be causing severe delays calling the information from the server database due to network lag.

Even when I copy a 70mb file from the server to each of the clients it can take 10 minutes. When I transfer it between client to client it is almost instant. So I really can't figure out why the server to client connection is so slow.

I have googled the pants out of this, disabled TCP Auto-Tuning, disabled Large Send Offload (LSO), turned off IPv6 networking as still using IPv4 and cleared DNS.

Still cannot transfer files across quickly and this is having a seriously detrimental effect on workload.

Does anyone know anything that could be causing this?

DragonQ · 29 Nov 2016 at 22:37

Are they actually syncing at 1 Gb/s? What does iPerf show the network speed between each PC as?

Liquid_Entity · 29 Nov 2016 at 22:47

How do I use iPerf. Not ever used it before.

Liquid_Entity · 29 Nov 2016 at 23:00

ok think I worked it out so the results below are the server running iperf3 -s and then I ran iperf3 -c IP of clients and the results are below. 60Mb/sec roughly

C:\iperf>iperf3 -s
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------
Accepted connection from .35, port 49472
[ 5] local .34 port 5201 connected to .35 port 49473
[ ID] Interval Transfer Bandwidth
[ 5] 0.00-1.00 sec 6.68 MBytes 56.0 Mbits/sec
[ 5] 1.00-2.00 sec 7.87 MBytes 66.0 Mbits/sec
[ 5] 2.00-3.00 sec 7.82 MBytes 65.6 Mbits/sec
[ 5] 3.00-4.00 sec 8.05 MBytes 67.5 Mbits/sec
[ 5] 4.00-5.00 sec 7.87 MBytes 66.0 Mbits/sec
[ 5] 5.00-6.00 sec 7.85 MBytes 65.8 Mbits/sec
[ 5] 6.00-7.00 sec 7.93 MBytes 66.5 Mbits/sec
[ 5] 7.00-8.00 sec 7.84 MBytes 65.8 Mbits/sec
[ 5] 8.00-9.00 sec 8.07 MBytes 67.7 Mbits/sec
[ 5] 9.00-10.00 sec 7.88 MBytes 66.1 Mbits/sec
[ 5] 10.00-10.13 sec 991 KBytes 64.9 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bandwidth
[ 5] 0.00-10.13 sec 0.00 Bytes 0.00 bits/sec sender
[ 5] 0.00-10.13 sec 78.8 MBytes 65.3 Mbits/sec receiver
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------
Accepted connection from .36, port 49325
[ 5] local .34 port 5201 connected to .36 port 49326
[ ID] Interval Transfer Bandwidth
[ 5] 0.00-1.00 sec 6.40 MBytes 53.7 Mbits/sec
[ 5] 1.00-2.00 sec 7.88 MBytes 66.1 Mbits/sec
[ 5] 2.00-3.00 sec 7.60 MBytes 63.8 Mbits/sec
[ 5] 3.00-4.00 sec 5.43 MBytes 45.5 Mbits/sec
[ 5] 4.00-5.00 sec 7.48 MBytes 62.8 Mbits/sec
[ 5] 5.00-6.00 sec 7.84 MBytes 65.7 Mbits/sec
[ 5] 6.00-7.00 sec 7.65 MBytes 64.1 Mbits/sec
[ 5] 7.00-8.00 sec 7.90 MBytes 66.3 Mbits/sec
[ 5] 8.00-9.00 sec 7.95 MBytes 66.7 Mbits/sec
[ 5] 9.00-10.00 sec 5.51 MBytes 46.3 Mbits/sec
[ 5] 10.00-10.18 sec 1.54 MBytes 71.9 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bandwidth
[ 5] 0.00-10.18 sec 0.00 Bytes 0.00 bits/sec sender
[ 5] 0.00-10.18 sec 73.2 MBytes 60.3 Mbits/sec receiver
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------
Accepted connection from .42, port 49538
[ 5] local .34 port 5201 connected to .42 port 49539
[ ID] Interval Transfer Bandwidth
[ 5] 0.00-1.00 sec 6.32 MBytes 53.0 Mbits/sec
[ 5] 1.00-2.00 sec 7.68 MBytes 64.4 Mbits/sec
[ 5] 2.00-3.00 sec 7.98 MBytes 67.0 Mbits/sec
[ 5] 3.00-4.00 sec 7.94 MBytes 66.6 Mbits/sec
[ 5] 4.00-5.00 sec 7.57 MBytes 63.5 Mbits/sec
[ 5] 5.00-6.00 sec 8.05 MBytes 67.5 Mbits/sec
[ 5] 6.00-7.00 sec 7.92 MBytes 66.4 Mbits/sec
[ 5] 7.00-8.00 sec 7.70 MBytes 64.6 Mbits/sec
[ 5] 8.00-9.00 sec 7.70 MBytes 64.6 Mbits/sec
[ 5] 9.00-10.00 sec 8.02 MBytes 67.3 Mbits/sec
[ 5] 10.00-10.19 sec 1.44 MBytes 63.4 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bandwidth
[ 5] 0.00-10.19 sec 0.00 Bytes 0.00 bits/sec sender
[ 5] 0.00-10.19 sec 78.3 MBytes 64.5 Mbits/sec receiver
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------

Liquid_Entity · 29 Nov 2016 at 23:07

More interestingly is when I use the client as the -s the speed is massively reduced

C:\iperf>iperf3 -c .37
Connecting to host .37, port 5201
[ 4] local .34 port 49320 connected to .37 port 5201
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-1.00 sec 315 KBytes 2.58 Mbits/sec
[ 4] 1.00-2.00 sec 189 KBytes 1.55 Mbits/sec
[ 4] 2.00-3.00 sec 378 KBytes 3.10 Mbits/sec
[ 4] 3.00-4.00 sec 189 KBytes 1.55 Mbits/sec
[ 4] 4.00-5.00 sec 252 KBytes 2.06 Mbits/sec
[ 4] 5.00-6.00 sec 252 KBytes 2.06 Mbits/sec
[ 4] 6.00-7.00 sec 315 KBytes 2.58 Mbits/sec
[ 4] 7.00-8.00 sec 378 KBytes 3.10 Mbits/sec
[ 4] 8.00-9.00 sec 315 KBytes 2.58 Mbits/sec
[ 4] 9.00-10.00 sec 315 KBytes 2.58 Mbits/sec
- - - - - - - - - - - - - - - - - - - - - - - - -
[ ID] Interval Transfer Bandwidth
[ 4] 0.00-10.00 sec 2.83 MBytes 2.37 Mbits/sec sender
[ 4] 0.00-10.00 sec 2.73 MBytes 2.29 Mbits/sec receiver

iperf Done.

bledd · 29 Nov 2016 at 23:22

List your network hardware and how they all connect.

Liquid_Entity · 29 Nov 2016 at 23:27

4 x dell 9020 computer running Windows 7 32 bit with Broadcom NetExtreme 1gb NIC installed
1 x Level1 5 port switch model GEU-0520
1 x Cisco Router (sorry don't know model number)
Possibly Cat 5e or CAT 6 cabling but don't know for sure.

The thing is this setup is used across several different locations and yet this location is proving to be a nightmare.

Andy_82 · 30 Nov 2016 at 01:01

Liquid_Entity said:
4 x dell 9020 computer running Windows 7 32 bit with Broadcom NetExtreme 1gb NIC installed
1 x Level1 5 port switch model GEU-0520
1 x Cisco Router (sorry don't know model number)
Possibly Cat 5e or CAT 6 cabling but don't know for sure.

The thing is this setup is used across several different locations and yet this location is proving to be a nightmare.

You've probably thought of this, but Have you tried a different network cable for the server? from what i understand the client to client communication is fine, but client to server isn't, which suggests the server connection is the limiting factor. I would swap the cable first and then the switch if that didn't help.

DragonQ · 30 Nov 2016 at 09:24

60 Mb/s is still abysmal, let alone 2.3 Mb/s. Could be cabling for sure.

bledd · 30 Nov 2016 at 11:44

Does it go switch, patch lead, patch panel, wall port, patch lead ?

Try other wall ports / cables. Try a basic cable tester between the first patch lead and the last one. -Don't connect it to anything that has power (ie switch or server)

APM · 30 Nov 2016 at 12:25

Re boot the switch.

Liquid_Entity · 30 Nov 2016 at 12:29

DSL wall socket >patched> DSL Router >patched> 1gb Switch >patched> wall sockets x 4 >patched> PC x 4

I think the bottle neck is on the server patch/cabling as this used to be where a client was connected, we wouldn't have seen the speed errors there so much as a client. Going to swap the machines around to at least see if that proves speed issue.

bledd · 30 Nov 2016 at 12:58

edit, wrong thread.