fix(utils): use separate IPv4/IPv6 lookups to avoid AI_ADDRCONFIG filtering#39914
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yury-s wants to merge 1 commit intomicrosoft:mainfrom
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fix(utils): use separate IPv4/IPv6 lookups to avoid AI_ADDRCONFIG filtering#39914yury-s wants to merge 1 commit intomicrosoft:mainfrom
yury-s wants to merge 1 commit intomicrosoft:mainfrom
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…tering When dns.lookup() is called with family: 0, Node.js passes AI_ADDRCONFIG to getaddrinfo(), which on macOS filters out loopback addresses for a protocol family if no non-loopback interface for that family is active. This causes intermittent failures connecting to CDP endpoints on macOS when Chrome binds only to ::1 (IPv6) — the lookup may return only 127.0.0.1, leaving ::1 untried. Fix by doing separate family: 4 and family: 6 lookups (which do not use AI_ADDRCONFIG) and merging the results, ensuring both IPv4 and IPv6 addresses are always included. Fixes: microsoft/playwright-mcp#1482
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Test results for "tests 1"1 failed 3 flaky39041 passed, 845 skipped Merge workflow run. |
Contributor
Test results for "MCP"1 failed 6279 passed, 350 skipped Merge workflow run. |
pavelfeldman
approved these changes
Mar 28, 2026
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Summary
dns.lookup(host, { family: 0 })passesAI_ADDRCONFIGtogetaddrinfo(), which on macOS filters out loopback addresses for a protocol family when no non-loopback interface for that family is active (e.g. under VPN/WiFi changes)localhost, failing intermittently when Chrome binds exclusively to::1(IPv6)family: 4andfamily: 6lookups (which do not useAI_ADDRCONFIG) and merge resultsFixes microsoft/playwright-mcp#1482