Operation in PPPoE/PPTP/L2TP/IPIP/GRE (including ERSPAN) tunnels

By default, DPI does not parse tunnels (tagged VLAN/QINQ and MPLS traffic are not considered tunnels), since tunnels may carry traffic from different operators or customers with conflicting IP sets. However, in non-standard deployments (before BRAS), tunnel parsing is required.

In the Lawful Interception prefilter, tunnel parsing is enabled automatically when the tap_dev parameter is present.
In other cases, tunnel parsing must be explicitly enabled using a configuration parameter in the file /etc/dpi/fastdpi.conf:

check_tunnels=1

This parameter enables parsing of PPPoE/PPTP/L2TP/IPIP/GRE (including ERSPAN) tunnels.