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EC2 OS/Kernel Symptom Diagnostic Troubleshooter (Part 2)

Use the interactive troubleshooter below to identify your EC2 OS/kernel symptom, review the raw evidence, understand the root cause, and apply the recommended fix.

🚨 Step 1: What specific error symptom are you experiencing?

Please click the most accurate description:


Quick Reference Table

#ScenarioKey Error SignalRoot CauseThe Fix
5Network packets dropped and new connections fail to establishethtool -S eth0 showing conntrack_allowance_exceededConnection tracking exceeded the maximum allowance for the instance type, preventing new connections from being established.N/A
6ENA Express falls back to standard ENA transmission, increasing the possibility of dropped packetsethtool -S eth0 | grep ena_srd showing high ena_srd_resource_utilizationThe network card attached to the instance has used up its maximum memory utilization for concurrent SRD connections.N/A
7Eligible outgoing SRD packets fall back to standard ENA transmissionSignificant differences between ena_srd_eligible_tx_pkts and ena_srd_tx_pktsAn eligible packet is over the maximum transmission unit (MTU) limit, causing it to fall back to standard ENA transmission.sudo ip link set dev eth0 mtu 8900
8Traffic to the DNS service, Instance Metadata Service, or Amazon Time Sync Service is droppedethtool -S eth0 showing linklocal_allowance_exceededThe packet-per-second (PPS) traffic to local proxy services exceeded the maximum allowance for the network interface.N/A