First, connect 'vasexperts' repository:

rpm --import http://vasexperts.ru/centos/RPM-GPG-KEY-vasexperts.ru
rpm -Uvh http://vasexperts.ru/centos/6/x86_64/vasexperts-repo-1-0.noarch.rpm

Optionally: upgrade OS components without kernel upgrade:

yum –exclude=kernel* update

If you perform the kernel upgrade anyway, you have to restart the computer after upgrade. Repairment actions may be required in some cases:
If the drivers' types of DPI and control network interfaces are the same, the control network access to the server is lost after the upgarde. In order to recover from this position, one needs to have the console access and use the instruction
If your network card supports Bypass: please restore bypass driver (item 2)

Upgrade DNA driver and observe its type. Take care to install the right driver, otherwise the network control interface may be lost.

yum install dna-ixgbe

or

yum install dna-igb

Reboot the computer or load the driver manually1) If you have occasionally upgraded drivers before OS reboot, please reinstall them and start the interfaces: yum reinstall dna-ixgbe
modprobe ixgbe
ifup dna0
ifup dna1 Make sure to take your driver's type and your interfaces into account.

Upgrade DPI software:

yum install fastdpi dpiutils

Add configuration parameter scale_factor for vertical scaling of the platform depending on the processing traffic. Its value equals approximately to the total bandwidth. This value varies in range from 1 to 10 (1 is for 1G channel, 10 is for 10G channel and more).

echo "scale_factor=10" >> /etc/dpi/fastdpi.conf

Restart the software:

service fastdpi restart

Check by top that the service has started. In case it did not: follow these instructions Troubleshooting or contact tech support. The remote access is required in the second case.

Remove the old versions of the software:

rm /usr/sbin/fastdpi_*