Troubleshooting Tip: Troubleshooting file upload issues on small FortiGates (less than 2GB of memory) using a PPPoE scope

[wcruvinel]

Description	This article describes troubleshooting steps for resolving file upload issues on small FortiGate devices (less than 2GB of memory) using PPPoE. Users may experience issues where PDF (or any other large file) uploads fail when using FortiGate devices (less than 2GB of memory) as the central firewall. This problem is often observed when the Internet connection is terminated on the FortiGate using PPPoE, with the FortiGate directly connected to the ISP modem operating in bridge mode. The issue is more frequent if the user has an xDSL connection with an upload capacity equal to or below 1Mbps.
Scope	Small FortiGates (less than 2GB of memory).
Solution	When the scenario described above exists, the following symptoms are typically observed: High CPU and memory usage on the FortiGate during file uploads. PPPoE connection flapping between the FortiGate and the PPPoE server. Recommended solution. To address this issue, install the optimization script below to free up resources (CPU and memory) and adjust the LCP timers. Script for optimization to free up resources (CPU and memory) and adjust the LCP timers: config system global set memory-use-threshold-extreme 97 set memory-use-threshold-green 90 set memory-use-threshold-red 95 set reset-sessionless-tcp disable set tcp-halfclose-timer 30 set tcp-timewait-timer 0 set tcp-rst-timer 5 set udp-idle-timer 60 set miglogd-children 1 set sslvpn-max-worker-count 2 set wad-worker-count 2 set scanunit-count 2 end config system autoupdate schedule     set status disable end config ips global set engine-count 2 set socket-size 32 set np-accel-mode none set exclude-signatures none end config system session-ttl set default 300 config port edit 0 set protocol 17 set timeout 10 set end-port 53 set start-port 53 next end end config system dns set dns-cache-limit 600 end config system fortiguard set webfilter-cache-ttl 600 set antispam-cache-ttl 600 end config system automation-action edit "RestartWAD" set action-type cli-script set minimum-interval 5 set script "diag test app wad 99" set accprofile "super_admin" next end config system automation-trigger edit "Enters Conserve Mode" set event-type low-memory next end config system automation-stitch edit "Restart WAD during Conserve Mode" set trigger "Enters Conserve Mode" config actions edit 1 set action "RestartWAD" set required enable next end next end config system auto-script edit restart_IPSengine set interval 43200 set repeat 356 set start auto set script 'diagnose test application ipsmonitor 99' next end config system interface edit "wan1" <- Insert the PPPoE interface. set vdom "root" set mode pppoe set lcp-echo-interval 30 set lcp-max-echo-fails 20 next end If the steps above do not fix the issue, check the articles below for help with troubleshooting performance problems related to Internet capacity and quality.  If a low-end device (with less than 2 GB of RAM) is being used, make sure to follow the recommended FortiOS version and capacity limits: Technical Tip: Low throughput troubleshooting Technical Tip: Script for reducing memory usage in small FortiGates experiencing conserve mode Troubleshooting Tip: How high CPU usage should be investigated Troubleshooting Tip: Troubleshooting PPPoE connection failed