You can most certainly reset interface counters via the steps in sk61500. Just be aware that reloading a NIC device driver will cause an outage on *all* individual interfaces utilizing that particular driver, including no doubt (in true Murphy's Law fashion) the interface you are currently using for your SSH control connection into the firewall itself. Careful!
Kind of like copy/pasting ACL updates on a Cisco and your SSH session freezes up permanently, sparking a panicked sprint to the console...oops.
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