[Bug 352841] Re: SCP over IPv6 address is very Slow. Takes Hours

[Prasad Tadi]

Bryan,


My hardware is little more complicated, I will explain that below...  
But wants to make sure that I understood "Local Link".

Hope you are not referring to IPv4 address.
scp over IPv4 is fine. No issues at all. Only when I use the IPv6, it  
chokes.

scp /tmp/x.iso 172.16.109.50:/tmp     completes in less than 3 sec.  
So almost the same speed that you are referring to.

When I use the same two systems and use the second network card  
(IPv6), then it chokes.

ex:
	scp /tmp/x.iso [a:b:c:d::e]:/tmp/     FAILS or completes in 1+ Hr :-(


So The issue I am referring is all about the IPv6 network addresses.


Coming to my hardware....

It is all on a ESX server. All these VMs ( freebsd, Ubuntu Linux  
boxes are on a single ESX server with VMware VM's.)
Logically speaking they are all on a single Hardware.

I tried between Multiple VMs freeBSD to different Ubuntu Servers  
( within the same ESX and also VM resides in different ESX. No issues.

When I copy from one Ubuntu to other Ubuntu server using IPv6, then  
only the issues shows up.


I will attache/share  some more facts / data tomorrow.

HTH
Prasad


On Apr 2, 2009, at 8:45 PM, Bryan McLellan wrote:

> Using only linklocal addresses I've sustained near 40MB/s copying a  
> 10GB
> file in the following patterns:
>
> Ubuntu 8.10 -> Ubuntu 9.04
> Debian 4.0 -> Ubuntu 9.04
> Ubuntu 9.04 -> Ubuntu 8.10
>
> It seems more likely that your problem would be a hardware issue.
>
> Have you tried connecting the two Ubuntu machines directly together to
> rule out any network equipment between the two?
>
> Have you tried to copy from your FreeBSD machine to more than one  
> Ubuntu
> server to rule out a problem with that installation or hardware?
>
> Any other testing that could possibly narrow it down? Thanks!
>
> -- 
> SCP over IPv6 address is very Slow. Takes Hours
> https://bugs.launchpad.net/bugs/352841
> You received this bug notification because you are a direct subscriber
> of the bug.
>
> Status in “openssh” source package in Ubuntu: New
>
> Bug description:
> Binary package hint: openssh-server
>
> Hi,
>
> I am using Ubutu Hardy release 8.04 and openssh 4.7P1
>
>
> lsb_release -a
> No LSB modules are available.
> Distributor ID: Ubuntu
> Description:    Ubuntu 8.04.1
> Release:        8.04
> Codename:       hardy
> root at htaf1:~#
> OpenSSH_4.7p1 Debian-8ubuntu1.2, OpenSSL 0.9.8g 19 Oct 2007
>
>
> When I copy a 50+ MB file from one system to another  Ubuntu
>
> Using IPv4 address  it took just less than 3 sec.
> Same thing over IPv6 took more than an hour ( 1 Hr and 20 Min)
>
> I copied the file using local IPv6 address. It ran fine. May be it  
> is using loop back, instead of real IPv6 address
>
>
> When I initiate the same from a free BSD box to BSD It took less  
> than 3 sec on both Ipv4 and IPv6.
> I can also copy from Ubuntu to a FreeBSD box faster both Ipv4 and  
> IPv6 addreses.
>
> I just can't copy the same from a Ubutu to Ubutu or other machines  
> to Ubuntu over IPv6 address.
>
> It is very critical for our product :-(
>
> I even tried getting the latest OpenSSH package from openssh.org  
> and compiled that module and ran that sshd.
> Still no use. Same old behaviour.
>
> It starts negotiating at 1.5 Mb/ sec and slowly drops to few KB /  
> sec and stalls the copy process during the time.
>
> Any updates or known issues.
>
> thanks in advance for your information on this issue.

====== Together we can build a better process =======
Prasad Tadi
ptadi at roshitech.com
http://www.roshitech.com
Fax: (270) 568-6295
cell: 603-809-7186

-- 
SCP over IPv6 address is very Slow. Takes Hours
https://bugs.launchpad.net/bugs/352841
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