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migrating-sing-box-configs

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Use when migrating sing-box configuration files between versions, when `sing-box check` reports deprecated fields or validation errors after an upgrade, or when a config written for an older sing-box version fails to work with a newer version.

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Migrating Sing-Box Configs

Overview

Sing-box deprecates and removes configuration fields across versions. This skill covers the migration patterns for versions 1.8.0 through 1.14.0, with a mandatory sing-box check verification step after each migration.

Core Workflow

  1. Identify the current config version and the target version
  2. Apply migrations sequentially from old to new (e.g. 1.8 → 1.10 → 1.11 → 1.12 → 1.14)
  3. After each migration step, run sing-box check -c <config> to verify
  4. If sing-box check fails, fix the reported errors before proceeding

Mandatory Verification

After every migration change, run:

sing-box check -c /path/to/config.json

Never skip this step. A passing sing-box check is the only reliable indicator that the config is valid for the target version.

If the binary for the target version is not installed, install it first or use -D to specify a different working directory. Ask the user which version they are targeting and how to obtain the correct binary.

When the Skill Doesn't Know a Configuration

If encountering a config field or migration not covered here, ask the user for:

  1. The sing-box docs repository URL (e.g. a local clone of https://github.com/SagerNet/sing-box on the docs branch)
  2. The official website URL (https://sing-box.sagernet.org) for the current documentation
  3. The specific source and target versions involved

Use WebFetch against the official site (https://sing-box.sagernet.org/migration/) for the latest migration guide, and https://sing-box.sagernet.org/configuration/ for current config reference.

Migration Reference

1.14.0 → current

Inline ACME to certificate provider

tls.acme → tls.certificate_provider (inline) or certificate_providers[] top-level array with tls.certificate_provider: "<tag>".

// Before
{ "tls": { "enabled": true, "acme": { "domain": ["example.com"], "email": "a@b.com" } } }

// After (inline)
{ "tls": { "enabled": true, "certificate_provider": { "type": "acme", "domain": ["example.com"], "email": "a@b.com" } } }

// After (referenced)
{ "certificate_providers": [{ "type": "acme", "tag": "my-cert", "domain": ["example.com"], "email": "a@b.com" }],
  "tls": { "enabled": true, "certificate_provider": "my-cert" } }

Address filter fields to response matching

DNS rules using rule_set with ip_cidr items → wrap with evaluate action + match_response: true.

// Before: DNS rule referencing geoip rule-set
{ "rule_set": "geoip-cn", "action": "route", "server": "local" }

// After: add evaluate action before the rule
{ "action": "evaluate", "server": "remote" },
{ "match_response": true, "rule_set": "geoip-cn", "action": "route", "server": "local" }

DNS: remove independent_cache

Simply delete the field — DNS cache now always keys by transport name.

DNS: store_rdrc → store_dns

In experimental.cache_file: rename store_rdrc: true → store_dns: true.

DNS: ip_version / query_type behavior

These fields now apply on every DNS rule evaluation (not just client queries). They are incompatible with legacy address filter fields in the same config. Migrate to evaluate + match_response first (see above).

1.12.0 → 1.13+

DNS server address → type

The address field with URI scheme prefixes is replaced by type + server:

Old addressNew typeNew server
"local""local"(none)
"tcp://1.1.1.1""tcp""1.1.1.1"
"1.1.1.1""udp""1.1.1.1"
"tls://1.1.1.1""tls""1.1.1.1"
"https://dns.google/dns-query""https""dns.google"
"quic://1.1.1.1""quic""1.1.1.1"
"h3://1.1.1.1/dns-query""h3""1.1.1.1"
"dhcp://auto""dhcp"(none)
"dhcp://en0""dhcp""interface": "en0"
"fakeip""fakeip"(none; inet4_range/inet6_range move into server)
"rcode://refused"(removed)Use action: "predefined" with rcode in a DNS rule

Additional changes:

  • address_resolver → domain_resolver on the server
  • strategy on server → strategy on DNS rule, or dns.strategy as default
  • client_subnet on server → client_subnet on DNS rule

Outbound DNS rules → domain_resolver

Remove dns.rules entries with outbound field. Add domain_resolver to the outbound's dial fields, or set route.default_domain_resolver.

// Before
{ "dns": { "rules": [{ "outbound": "any", "server": "local" }] } }

// After — per-outbound
{ "outbounds": [{ "type": "socks", "server": "example.org", "server_port": 2080,
    "domain_resolver": { "server": "local", "rewrite_ttl": 60 } }] }

// After — global default
{ "route": { "default_domain_resolver": { "server": "local" } } }

domain_strategy → domain_resolver

In outbound dial fields: remove domain_strategy, add domain_resolver with strategy.

// Before
{ "domain_strategy": "prefer_ipv4" }

// After
{ "domain_resolver": { "server": "local", "strategy": "prefer_ipv4" } }

1.11.0 → 1.12+

Legacy special outbounds → rule actions

OldNew
"type": "block" outbound + route ruleRoute rule with "action": "reject"
"type": "dns" outbound + route ruleRoute rule with "action": "hijack-dns"

Remove the block/dns outbound entirely, use rule actions instead.

Legacy inbound fields → rule actions

Move sniff, sniff_timeout, domain_strategy from inbound config into route rules keyed by inbound tag.

// Before
{ "inbounds": [{ "type": "mixed", "sniff": true, "sniff_timeout": "1s", "domain_strategy": "prefer_ipv4" }] }

// After
{ "inbounds": [{ "type": "mixed", "tag": "in" }],
  "route": { "rules": [
    { "inbound": "in", "action": "resolve", "strategy": "prefer_ipv4" },
    { "inbound": "in", "action": "sniff", "timeout": "1s" }
  ] } }

Destination override → route options

Move override_address / override_port from direct outbound to route rules with action: "route-options".

// Before
{ "outbounds": [{ "type": "direct", "override_address": "1.1.1.1", "override_port": 443 }] }

// After
{ "route": { "rules": [{ "action": "route-options", "override_address": "1.1.1.1", "override_port": 443 }] } }

WireGuard outbound → endpoint

Move from outbounds[{type:"wireguard"...}] to endpoints[{type:"wireguard"...}]. Key field renames:

Old (outbound)New (endpoint)
server / server_portpeers[].address / peers[].port
local_addressaddress
peer_public_keypeers[].public_key
pre_shared_keypeers[].pre_shared_key
reservedpeers[].reserved
system_interfacesystem
interface_namename
mtumtu

1.10.0 → 1.11+

TUN address merge

Merge inet4_address/inet6_address → address, same for route_address and route_exclude_address.

// Before
{ "inet4_address": "172.19.0.1/30", "inet6_address": "fdfe:dcba:9876::1/126",
  "inet4_route_address": ["0.0.0.0/1"], "inet6_route_address": ["::/1"] }

// After
{ "address": ["172.19.0.1/30", "fdfe:dcba:9876::1/126"],
  "route_address": ["0.0.0.0/1", "::/1"] }

1.9.0 → 1.10

domain_suffix behavior change

Values not prefixed with . now match (domain|.+\.domain) instead of literal prefix. Add . prefix to preserve old behavior, or verify intent.

process_path on Windows

Format changed from device path (\Device\HarddiskVolume1\...) to Win32 path (C:\...). Update all process_path values accordingly.

1.8.0 → 1.9+

Clash API cache → independent cache_file

Move experimental.clash_api.cache_file, cache_id, store_fakeip into experimental.cache_file. Add "enabled": true.

// Before
{ "experimental": { "clash_api": { "cache_file": "cache.db", "store_fakeip": true } } }

// After
{ "experimental": { "cache_file": { "enabled": true, "path": "cache.db", "store_fakeip": true } } }

GeoIP → rule-sets

Replace route.geoip, route.rules[].geoip, route.rules[].source_geoip with rule_set entries and rule_set rule references.

  • geoip: "private" → "ip_is_private": true
  • geoip: "cn" → "rule_set": "geoip-cn" + remote rule-set definition
  • source_geoip → rule_set_ipcidr_match_source: true on the rule
  • Use sing-box geoip export to convert custom GeoIP databases

Requires experimental.cache_file.enabled: true for rule-set caching.

Geosite → rule-sets

Replace route.geosite, route.rules[].geosite with rule_set references.

// Before
{ "route": { "rules": [{ "geosite": "cn", "outbound": "direct" }],
    "geosite": { "download_detour": "proxy" } } }

// After
{ "route": { "rules": [{ "rule_set": "geosite-cn", "outbound": "direct" }],
    "rule_set": [{ "tag": "geosite-cn", "type": "remote", "format": "binary",
      "url": "https://raw.githubusercontent.com/SagerNet/sing-geosite/rule-set/geosite-cn.srs",
      "download_detour": "proxy" }] },
  "experimental": { "cache_file": { "enabled": true } } }

Common Mistakes

  • Skipping intermediate versions. Migrate step by step. A 1.8 config cannot jump directly to 1.14.
  • Not running sing-box check after each step. Each migration introduces changes that depend on prior steps being correct.
  • Forgetting experimental.cache_file.enabled: true when migrating to rule-sets.
  • Rcode server removal. rcode://refused DNS servers are gone; replace with action: "predefined" DNS rules with rcode field. Alternatively, use a DNS rule with action: "reject".
  • WireGuard endpoint address. The endpoint's address is the interface's own address, NOT the outbound's local_address. The peer address goes into peers[].address.
  • Using ENABLE_DEPRECATED_LEGACY_DNS_SERVERS=true env var. This masks real migration errors. Always fix the config instead.
  • Not tagging DNS servers. When migrating to domain_resolver, DNS servers referenced by tag (e.g. domain_resolver: "tcp-dns") must have a tag field set.

Red Flags

  • Editing a config without knowing the source version — ask the user first
  • Migrating without sing-box check available — install the target binary first
  • Encountering unknown fields — ask for docs URLs, do not guess
  • sing-box check passes only with ENABLE_DEPRECATED_* env var — the config is still broken
  • domain_resolver references a DNS server without a tag — add tag to the server
  • Making changes without running sing-box check — every change must be verified