fix(controller): enable ARP learning on VPC routers that have peerings - #6882
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Pull request overview
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Updates VPC handling logic so ARP learning behavior is enabled when VPC peerings are configured, not only when external networking is enabled.
Changes:
- Extend
learnFromARPRequestcondition to also consider presence ofvpc.Spec.VpcPeerings.
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| } | ||
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| learnFromARPRequest := vpc.Spec.EnableExternal | ||
| learnFromARPRequest := vpc.Spec.EnableExternal || len(vpc.Spec.VpcPeerings) != 0 |
| } | ||
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| learnFromARPRequest := vpc.Spec.EnableExternal | ||
| learnFromARPRequest := vpc.Spec.EnableExternal || len(vpc.Spec.VpcPeerings) != 0 |
VPC peering requires ARP learning on the logical router. Cross-VPC traffic arrives via the peer LRP, so the destination router needs to learn pod MACs from ARP requests. Without it, packets are mis-forwarded (tunneled instead of local delivery). Previously, learnFromARPRequest was only set for EnableExternal and U2O interconnection. This patch also enables it when any VpcPeerings exist. Signed-off-by: Apinant U-suwantim <Hello@Apinant.dev>
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Coverage Report for CI Build 27737245944Coverage remained the same at 26.652%Details
Uncovered ChangesNo uncovered changes found. Coverage RegressionsNo coverage regressions found. Coverage Stats
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oilbeater
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#6882) VPC peering requires ARP learning on the logical router. Cross-VPC traffic arrives via the peer LRP, so the destination router needs to learn pod MACs from ARP requests. Without it, packets are mis-forwarded (tunneled instead of local delivery). Previously, learnFromARPRequest was only set for EnableExternal and U2O interconnection. This patch also enables it when any VpcPeerings exist. Signed-off-by: Apinant U-suwantim <Hello@Apinant.dev> (cherry picked from commit 70fe403)
oilbeater
pushed a commit
that referenced
this pull request
Jun 18, 2026
#6882) VPC peering requires ARP learning on the logical router. Cross-VPC traffic arrives via the peer LRP, so the destination router needs to learn pod MACs from ARP requests. Without it, packets are mis-forwarded (tunneled instead of local delivery). Previously, learnFromARPRequest was only set for EnableExternal and U2O interconnection. This patch also enables it when any VpcPeerings exist. Signed-off-by: Apinant U-suwantim <Hello@Apinant.dev> (cherry picked from commit 70fe403)
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Description
VPC peering requires ARP learning on the logical router.
When traffic arrives from a peered VPC, it enters via the peer LRP. If
always_learn_from_arp_request=false, the destination pod's MAC is never learned intomac_binding, so the router mis-forwards the packet (tunnels it instead of delivering locally).Currently
learnFromARPRequestis only set forEnableExternaland the U2O interconnection case. This change also enables it when the VPC has anyVpcPeerings.Impact