Customer complaining of slow file transfer speed between 2 branch PC

[meyery2k]

Site has 6 branches in a hub spoke topography linked via PTP T1 circuits.  The hub provides Internet connection to all branches.  Type of business is a CU.  VoIP is implemented here.  IP phones at branches are connected to a PBX at the main branch which also serves as the PSTN gateway.

IT Admin was using VNC to remotely access a branch PC from a PC at the main site.  He performed a file transfer and noticed the speed was no better than dial up.  He asked me to take a look.  I can find no issues.  I pinged the PC at the branch from the router at the main being used as the default gateway and ping time was fine.  I checked the T1 interfaces at both sites and no errors in the past 24 hours.  I checked the switch port the PC at the branch is connected to and noted no unusual amount of errors.  My best guess is an issue with one of the PC but I have been asked to investigate this to the best of my ability.

Any ideas?  I don't believe there is a general network issue at either site.  If there was, I would expect VoIP to be affected.

Thank you in advance for your help ~ Mike

[Anonymous]

- Thanks for posting your question on the forum!

In troubleshooting an issue like this, the first thing to check is to make sure there aren't any physical errors on the interfaces. It sounds like you have already done this. If you could, please post your configuration for the main and remote site in question (remember to remove any sensitive information). I'd be more than happy to review the files and see if there's anything that might be problematic.

Are there any other PCs that seem to be experiencing the same slow file transfer as the one the IT admin noticed?

Please do not hesitate to let us know if you have any questions.

Thanks,

Noor

[meyery2k]

Noor,

Thank you for the kind offer.

Configs attached as well as a network diagram.

One of the configs is a Cisco just so you have the whole picture.

The file transfer took place between the main site (131.53.1.0/24) and Keaau (131.53.4.0/24)

As requested, login, password, and public IPs have been redacted.

Mike

[jayh]

Is the FastEthernet0 port on the Cisco set to half-duplex for a reason?  That's the gateway to the destination.  I would let it and the corresponding port on the NetVanta 3448 autonegotiate to 100-full, or if that fails hard-code them both to100/full.

On the Cisco CUHFCU_Hilo:

!

interface FastEthernet0

ip address 131.53.1.209 255.255.255.0

[snippage]

ip igmp query-interval 125

speed auto

half-duplex

!

Also, the Cisco shows its T1 clocking internally.

interface Serial1

description PTP to Keaau

ip address 10.10.11.1 255.255.255.252

[snippage]

service-module t1 clock source internal

!

Does the Adtran at CUHawaiiKeaau have its primary timing source set to T1 1/1?  If not it should.

[meyery2k]

Jay H,

I saw that. I have no idea why it is half-duplex. I am going to change to full when they are closed and then monitor for any errors. If there are then I will visit site and see why this is the case. Thank you for pointing this out.

The T1's clocking - These are point to point T1 and we are responsible for clocking so I always set my "main" site to provide clocking (internal) and the remote branches to get their clocking from the network.

I have had many the argument on this but when I set both sides to internal or network and the slips start, that quashes it....

Everything at the branch in .4 works well as far as I know. They have VoIP phones so if they were issues, it would be evident in the VoIP. The admin VNC'ed to a PC there and then did a file transfer via windows command line and the transfer speed was something like 7K per second.

[jayh]

meyery2k wrote:

The T1's clocking  - These are point to point T1 and we are responsible for clocking so I always set my "main" site to provide clocking (internal) and the remote branches to get their clocking from the network.

Understandable and that's exactly how I would do it as well.  I didn't see a "system-timing" or other command in the config of CUHawaiiKeaau showing clock sourced from the T1 1/1 interface. Do you have errors or CSS when looking at the interfaces? 

Everything at the branch in .4 works well as far as I know.  They have VoIP phones so if they were issues, it would be evident in the VoIP.  The admin VNC'ed to a PC there and then did a file transfer via windows command line and the transfer speed was something like 7K per second.

Clock slips don't affect VoIP as severely because of the small packet sizes.

If the duplex setting and verifying T1 timing doesn't fix it, try a 1500-byte ping (1472 if less ethernet header) with DF set to see if something is choking MTU.  Iperf is a useful tool to troubleshoot this type of thing.

[meyery2k]

Jayh

Thanks for the advice.

T1 - No slips or errors on either side. No clocking statement means the T1 will get it's clocking from the network.

I will try the ping suggestion if changing the FE port on the Cisco does not help.

[Anonymous]

:

I went ahead and flagged this post as "Assumed Answered." If any of the responses on this thread assisted you, please mark them as Correct or Helpful as the case may be with the applicable buttons. This will make them visible and help other members of the community find solutions more easily. If you still need assistance, we would be more than happy to continue working with you on this - just let us know in a reply.

Thanks,

Levi