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Always-Free instance: SSH via IPv4 works, but no outbound IPv4 traffic (ICMP/TCP/UDP). IPv6 OK. Need OCI support.

Yuchen WangJul 22 2025

Hello Oracle Cloud Infrastructure team,

I’m running an Always-Free VM in ca-toronto-1 with the following details:

  • Instance OCID
    ocid1.instance.oc1.ca-toronto-1.an2g6ljrqoo33uqcva5tlguiwwxnfepydtl5t46t53q4hx2qisglgwr6h4sa
  • Private IP
    10.0.0.102
  • Reserved Public IP
    129.153.60.57
  • Subnet
    subnet12240344 (public, CIDR 10.0.0.0/24)
  • Security Lists / Network ACLs / Source-Destination Check
    All verified and allow all outbound IPv4 traffic.
  • Route Table
    Default route table: 0.0.0.0/0 → Internet Gateway
  • Symptoms
    • SSH via IPv4 works fine (I can connect to 129.153.60.57).
    • Outbound IPv4 fails: ping -c 4 8.8.8.8 shows 100 % packet loss, curl -4 https://ifconfig.me times out.
    • tcpdump on enp0s6 only sees ICMP echo requests going out; no replies.
    • IPv6 outbound works perfectly.
  • Steps already tried
    • Flushed all iptables/nftables rules.
    • Re-associated the default route table.
    • Rebooted the instance.
    • Lowered MTU to 1500.

Request
Please check the platform-layer Internet Gateway / NAT rule for this subnet to ensure IPv4 egress is correctly forwarded.

Appreciate any guidance or backend checks you can provide.

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Added on Jul 22 2025
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