Simpler Navigation for Servers and Operating Systems - Please Update Your Bookmarks
Completed: a much simpler Servers and Operating Systems section of the Community. We combined many of the older boards, so you won't have to click through so many levels to get at the information you need. Check the consolidated boards here as many sub-forums are now single boards.
If you have bookmarked forums or discussion boards in Servers and Operating Systems, we suggest you check and update them as needed.
Networking
cancel
Showing results for 
Search instead for 
Did you mean: 

Data Transfer rate "Fluctuation" using scp/sftp through Virtual Connect

BE_UNIX_PROD
Occasional Contributor

Data Transfer rate "Fluctuation" using scp/sftp through Virtual Connect

Hello,

 

We are facing this issue and after trying for almost two weeks, no solution has been found yet. So any pointers in the right direction would be very highly appreciated. 

 

Architecture: Recently we have migrated two servers to the new integrity based infrastructure. There are two blades BL890C, in SG cluster, using Virtual Connect Flex-10. The cluster pkg is BC volume of Billing DB. They need to talk with DWH servers for fetching data for reports etc. DWH servers are located in another physical location and have a different vlan. Blades have HP-UX 11.31, while DWH servers have 11.23.

 

The Problem: While transfering data from Billing to DWH, data transfer rate fluctuates so much that its almost useless. It ranges from 10 MBps to 64 KBps, and its just random. i.e. it doesn't decrease/increase continuosly. In one instance its 8 MBps and next would be 500 KBps and so on. The problem is with one-sided data transfer, meaning that transfer from DWH to these servers is almost constant at 10 MBps. Also, there is no problem while transfering withing the same data center or same subnet. 

 

It would look like a basic case of network optimization or something to do with network infrastructure, but our network admins have ruled everything out from their end. They said everything is ok, although we have no details of their tests. The problem is so serious now that management is even thinking to role back the project (migrate back to old servers). Since no one seems to know too much about Virtual Connect, so all fingers are being pointed at it...!!! 

 

I'd provide any details necessary to make an analysis. We've even tried to tinker with TCP parameters, ssh parameters, turned off FlowControl in VC etc. But nothing has worked so far. 

 

Thanking in anticipation!

 

Hassan Gilani

Milan, Italy

BE Unix Prod BSS
3 REPLIES
Dennis Handly
Acclaimed Contributor

Re: Data Transfer rate "Fluctuation" using scp/sftp through Virtual Connect

Do you have a way to test it without the encryption of scp/sftp?  I.e. you may have CPU vs networking issues.

BE_UNIX_PROD
Occasional Contributor

Re: Data Transfer rate "Fluctuation" using scp/sftp through Virtual Connect

For the purpose of testing, I've shifted the BC pkg to the other node, so the server is currently doing nothing at all. I don't think it could be CPU problem in such case. Also I've observed the CPU utilization during the transfer and its absolutely normal. 

BE Unix Prod BSS
BE_UNIX_PROD
Occasional Contributor

Re: Data Transfer rate "Fluctuation" using scp/sftp through Virtual Connect

Gurus, please help me out in this issue... I've truly lost my way and am out of anymore options to think.

BE Unix Prod BSS