Unless there is anything obvious, such as running out of disks space, troubleshooting your problem will require a lot more technical info and research. Your problem is most likely also not Oracle Linux, but VirtualBox, which has it's own forum at https://forums.virtualbox.org/
For what it's worth, I used the latest version of VirtualBox 4.3.6 only for a few hours and found out that my network connection (bridged adapter, virtio-net) would frequently pause for several minutes when doing long data transfers, and it even froze the network of the host system. I changed back to 4.2.22 and everything is fine again.
Hi. Thanks for your quick answer. I even could not imagine that the reason may be in Virtual Box version. But it looks like on the truth.
I think this is not an issue connected with not enough quantity of disk space, as i am checking it each time before copying of the data.
I will try to downgrade Virtual Box up to the mentioned version 4.2.22 (as i am using now 4.3.6 version too) and will check once again.
After downgrade VirtualBox up to 4.2.22 looks like issue with connection is not appears anymore.
Thanks for the help.
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