Disable default route installed in dpu #24495
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/azp run Azure.sonic-buildimage |
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Azure Pipelines successfully started running 1 pipeline(s). |
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hi @prsunny and @prabhataravind may we have a reviewer added please? |
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/azp run Azure.sonic-buildimage |
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Azure Pipelines successfully started running 1 pipeline(s). |
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@yue-fred-gao I recall this was fixed in the past. See below PRs. You can just remove the gateway config from smartswitch DHCP config and the default route should not get programmed. Could you check that instead of adding a smartswitch specific check? |
prabhataravind
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Nov 15, 2025
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prabhataravind
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prabhataravind
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Could we just remove gateway from smartswitch DHCP_SERVER_IPV4 default config?
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Why I did it
DPU in smartswitch uses dhcp to get ip for its midplane interface. The interface is only for management traffic. Data traffic should go through Ethernet interface, which is where the default route should be. So we should not install a default route by dhcp over the midplane interface. It will disrupt data traffic.
Work item tracking
How I did it
Change dhcp server in smart-switch not to send "routers" option to dhcp client.
How to verify it
Reboot dpu or renew dhcp lease and verify no default route installed into dpu.
Which release branch to backport (provide reason below if selected)
Tested branch (Please provide the tested image version)
Description for the changelog
Link to config_db schema for YANG module changes
A picture of a cute animal (not mandatory but encouraged)