Support Knowledge Base Firewalls

UpdatedJune 7, 2021

How to Troubleshoot Packet Drops and ISP/WAN Connectivity Issues

Description

This article will list all initial and most common configuration you can apply when facing issues with packet drops or ISP throughput.

Resolution

Pre-Requisites:	Explanation of Drop Code and Module ID Values
Troubleshooting (Packet Drops):	How Do I Resolve Drop Code: Packet Dropped Policy Drop? Packet Capture Shows Packet Dropped: Connection Cache Add Failed Packets Dropped with Enforced Firewall Rule Packet Dropped as IP Sanity Test Failed Troubleshooting Content Filter Drops Packet Dropped: UDP and ICMP Flood Protection How Can I Resolve Drop Code IP Spoof? Packet Dropped: DNS Rebind Attack The Log Shows Received Packet Retransmission Drop Duplicate Packet Log Message Indicates Malformed or Unhandled IP Packets Dropped Dropped Packets Because of Invalid TCP Flag Drop Packet: NAT Remap obtained Invalid Translated Source From Original Offset
Troubleshooting (VPN):	Troubleshooting VPN Packet Drops with Drop Code Message: Octeon Decryption Failed SSLVPN feature: NetExtender Packets Dropped with Enforced Firewall Rule or Policy Drop Drop Code: 338, Octeon Decryption Failed for Inbound Packet Log Shows IPSec Packet To or From Illegal Host
Troubleshooting (ISP Connectivity):	Troubleshooting PPTP ISP connectivity issues Troubleshooting L2TP ISP Connectivity issues Troubleshooting PPPOE ISP Connectivity Issues
Troubleshooting (ISP Throughput):	Troubleshooting Network Throughput, Latency and Bandwidth Issues with a SonicWALL How Can I Troubleshoot Slow Internet Speeds in SonicWALL Firewall? Tips For Troubleshooting Speed and Throughput Issues on a SonicWALL Firewall How To Use IPERF To Measure Throughput on a SonicWALL Firewall

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