Network problems while running VirtualBox

[Peter Ross]

Quoting "Gustau Pérez" <gperez at entel.upc.edu>:

> Al 13/07/2011 23:57, En/na Peter Ross ha escrit:
>> I have a problem with the network while running VirtualBox.
>>
>> As soon as I _run_ a VirtualBox I am not able to copy large files  
>> (e.g. virtual disks or ZFS snapshots) using ssh/scp to another  
>> machine.
>>
>> The ssh crashes with "Write failed: Cannot allocate memory"
>>
>> thrown by a write(2) in /usr/src/crypto/openssh/roaming_common.c  
>> (in function roaming_write). It returns the ENOMEM (an error it  
>> should never return, according to the mainpage;-)
>>
>> It is immediately working when I stop the VirtualBox, even if the  
>> VirtualBox kernel modules are still loaded.
>> ..
>> I experienced the problem with VirtualBox 3.2 first but the upgrade  
>> to VirtualBox 4.0.8 and the base system recently did not help.
>
>    I have AMD64/STABLE+virtualbox[4.0.10|4.1Beta] on a Dell R710  
> with two scenarios:
>
>     1.- Sending large files from the host to the guest with scp.
>     1,.  rsync+ssh in the host machine (with virtualbox) sending  
> large files to a remote machine.
>
>    in fact both scenarios are the same, the host machine sending  
> large chunks of data. Both fail as it fails to everyone in the list.
>
>    Ok. So far so good. To track down the problem I tested may  
> changes of configuration with STABLE (if you want the details please  
> let me know and I'll send them to the list). None did the trick. I  
> even tried communications between the host and the guest with  
> vboxnet. scp failed with the "no memory allocation" problem.
>
>    Now I tried AMD64/CURRENT+virtualbox 4.0.10 on a laptop. I tested  
> an scenario like the one described in number 1. It worked just fine.  
> In fact I tried something like this in the host machine just to be  
> sure:
>
>       # for i in {1..10}
>                do
>                      cat "large_file.data" | ssh -l root  
> 192.168.56.101 "cat -> /dev/null"
>                done
>
>     Where 192.168.56.101 is the guest machine (I'm using vboxnet).  
> This large file is 8 Gb file. So it gave me an 80Gb transfer. It  
> worked fine. This scenario would have failed with STABLE.
>
>    So I guess it has something to do with the combo  
> STABLE+Virtualbox. There must a change in CURRENT that doesn't  
> trigger the problem. I think it would be appropriate if anyone else  
> could also try with CURRENT.
>
>    As an addition I remember all of this worked with 8.1 and an  
> early version of virtualbox 3.2 series . But I can't say which  
> revision of 8.1 I had when I was using that kind of scenarios.

I experienced the problem first on VirtualBox 3.2 and  
FreeBSD-8.2-PRERELEASE. Marlon already in September 2010.

The laptop isn't the ultimate test as long as you haven't the same  
data going through the netgraph subsystem.

Can you try to set net.graph.maxdata as well (see my other e-mail).  
Does it solve your problem too?

Thanks for your help
Peter