refactor: v3 config options take precedence over v2 deprecated.

server/internal/config/capture.go

@@ -472,24 +472,28 @@ func (s *Capture) Set() {
 func (s *Capture) SetV2() {
 	deprecatedV2ConfigUsed := false
 
-	var ok bool
-
 	//
 	// video
 	//
 
 	if display := viper.GetString("display"); display != "" {
-		s.Display = display
+		if useV2Fallback("capture.video.display") {
+			s.Display = display
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_DISPLAY' which is deprecated, please use 'NEKO_CAPTURE_VIDEO_DISPLAY' and/or 'NEKO_DESKTOP_DISPLAY' instead, also consider using 'DISPLAY' env variable if both should be the same")
 		deprecatedV2ConfigUsed = true
 	}
 
 	modifiedVideoCodec := false
 	if videoCodec := viper.GetString("video_codec"); videoCodec != "" {
-		s.VideoCodec, ok = codec.ParseStr(videoCodec)
+		videoCodecValue, valid := codec.ParseStr(videoCodec)
-		if !ok || s.VideoCodec.Type != webrtc.RTPCodecTypeVideo {
+		if !valid || videoCodecValue.Type != webrtc.RTPCodecTypeVideo {
 			log.Warn().Str("codec", videoCodec).Msgf("unknown video codec, using Vp8")
-			s.VideoCodec = codec.VP8()
+			if useV2Fallback("capture.video.codec") {
+				s.VideoCodec = codec.VP8()
+			}
+		} else if useV2Fallback("capture.video.codec") {
+			s.VideoCodec = videoCodecValue
 		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_VIDEO_CODEC' which is deprecated, please use 'NEKO_CAPTURE_VIDEO_CODEC' instead")
 		deprecatedV2ConfigUsed = true
@@ -497,22 +501,30 @@ func (s *Capture) SetV2() {
 	}
 
 	if viper.GetBool("vp8") {
-		s.VideoCodec = codec.VP8()
+		if useV2Fallback("capture.video.codec") {
+			s.VideoCodec = codec.VP8()
+		}
 		log.Warn().Msg("you are using deprecated config setting 'NEKO_VP8=true', use 'NEKO_CAPTURE_VIDEO_CODEC=vp8' instead")
 		deprecatedV2ConfigUsed = true
 		modifiedVideoCodec = true
 	} else if viper.GetBool("vp9") {
-		s.VideoCodec = codec.VP9()
+		if useV2Fallback("capture.video.codec") {
+			s.VideoCodec = codec.VP9()
+		}
 		log.Warn().Msg("you are using deprecated config setting 'NEKO_VP9=true', use 'NEKO_CAPTURE_VIDEO_CODEC=vp9' instead")
 		deprecatedV2ConfigUsed = true
 		modifiedVideoCodec = true
 	} else if viper.GetBool("h264") {
-		s.VideoCodec = codec.H264()
+		if useV2Fallback("capture.video.codec") {
+			s.VideoCodec = codec.H264()
+		}
 		log.Warn().Msg("you are using deprecated config setting 'NEKO_H264=true', use 'NEKO_CAPTURE_VIDEO_CODEC=h264' instead")
 		deprecatedV2ConfigUsed = true
 		modifiedVideoCodec = true
 	} else if viper.GetBool("av1") {
-		s.VideoCodec = codec.AV1()
+		if useV2Fallback("capture.video.codec") {
+			s.VideoCodec = codec.AV1()
+		}
 		log.Warn().Msg("you are using deprecated config setting 'NEKO_AV1=true', use 'NEKO_CAPTURE_VIDEO_CODEC=av1' instead")
 		deprecatedV2ConfigUsed = true
 		modifiedVideoCodec = true
@@ -552,7 +564,9 @@ func (s *Capture) SetV2() {
 						GstPipeline: strings.Replace(pipeline, "show-pointer=true", "show-pointer=false", 1),
 					},
 				}
-				s.VideoIDs = []string{"main"}
+				if useV2Fallback("capture.video.ids") {
+					s.VideoIDs = []string{"main"}
+				}
 			}
 		}
 
@@ -569,17 +583,23 @@ func (s *Capture) SetV2() {
 	//
 
 	if audioDevice := viper.GetString("device"); audioDevice != "" {
-		s.AudioDevice = audioDevice
+		if useV2Fallback("capture.audio.device") {
+			s.AudioDevice = audioDevice
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_DEVICE' which is deprecated, please use 'NEKO_CAPTURE_AUDIO_DEVICE' instead")
 		deprecatedV2ConfigUsed = true
 	}
 
 	modifiedAudioCodec := false
 	if audioCodec := viper.GetString("audio_codec"); audioCodec != "" {
-		s.AudioCodec, ok = codec.ParseStr(audioCodec)
+		audioCodecValue, valid := codec.ParseStr(audioCodec)
-		if !ok || s.AudioCodec.Type != webrtc.RTPCodecTypeAudio {
+		if !valid || audioCodecValue.Type != webrtc.RTPCodecTypeAudio {
 			log.Warn().Str("codec", audioCodec).Msgf("unknown audio codec, using Opus")
-			s.AudioCodec = codec.Opus()
+			if useV2Fallback("capture.audio.codec") {
+				s.AudioCodec = codec.Opus()
+			}
+		} else if useV2Fallback("capture.audio.codec") {
+			s.AudioCodec = audioCodecValue
 		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_AUDIO_CODEC' which is deprecated, please use 'NEKO_CAPTURE_AUDIO_CODEC' instead")
 		deprecatedV2ConfigUsed = true
@@ -587,22 +607,30 @@ func (s *Capture) SetV2() {
 	}
 
 	if viper.GetBool("opus") {
-		s.AudioCodec = codec.Opus()
+		if useV2Fallback("capture.audio.codec") {
+			s.AudioCodec = codec.Opus()
+		}
 		log.Warn().Msg("you are using deprecated config setting 'NEKO_OPUS=true', use 'NEKO_CAPTURE_AUDIO_CODEC=opus' instead")
 		deprecatedV2ConfigUsed = true
 		modifiedAudioCodec = true
 	} else if viper.GetBool("g722") {
-		s.AudioCodec = codec.G722()
+		if useV2Fallback("capture.audio.codec") {
+			s.AudioCodec = codec.G722()
+		}
 		log.Warn().Msg("you are using deprecated config setting 'NEKO_G722=true', use 'NEKO_CAPTURE_AUDIO_CODEC=g722' instead")
 		deprecatedV2ConfigUsed = true
 		modifiedAudioCodec = true
 	} else if viper.GetBool("pcmu") {
-		s.AudioCodec = codec.PCMU()
+		if useV2Fallback("capture.audio.codec") {
+			s.AudioCodec = codec.PCMU()
+		}
 		log.Warn().Msg("you are using deprecated config setting 'NEKO_PCMU=true', use 'NEKO_CAPTURE_AUDIO_CODEC=pcmu' instead")
 		deprecatedV2ConfigUsed = true
 		modifiedAudioCodec = true
 	} else if viper.GetBool("pcma") {
-		s.AudioCodec = codec.PCMA()
+		if useV2Fallback("capture.audio.codec") {
+			s.AudioCodec = codec.PCMA()
+		}
 		log.Warn().Msg("you are using deprecated config setting 'NEKO_PCMA=true', use 'NEKO_CAPTURE_AUDIO_CODEC=pcma' instead")
 		deprecatedV2ConfigUsed = true
 		modifiedAudioCodec = true
@@ -613,11 +641,15 @@ func (s *Capture) SetV2() {
 
 	// audio pipeline
 	if modifiedAudioCodec || audioBitrate != 0 || audioPipeline != "" {
-		pipeline, err := NewAudioPipeline(s.AudioCodec, s.AudioDevice, audioPipeline, audioBitrate)
+		if useV2Fallback("capture.audio.pipeline") {
-		if err != nil {
+			pipeline, err := NewAudioPipeline(s.AudioCodec, s.AudioDevice, audioPipeline, audioBitrate)
-			log.Warn().Err(err).Msg("unable to create audio pipeline, using default")
+			if err != nil {
+				log.Warn().Err(err).Msg("unable to create audio pipeline, using default")
+			} else {
+				s.AudioPipeline = pipeline
+			}
 		} else {
-			s.AudioPipeline = pipeline
+			log.Warn().Msg("ignoring legacy audio pipeline settings because NEKO_CAPTURE_AUDIO_PIPELINE is already set")
 		}
 
 		if audioPipeline != "" {
@@ -633,22 +665,28 @@ func (s *Capture) SetV2() {
 	//
 
 	if viper.IsSet("broadcast_pipeline") {
-		s.BroadcastPipeline = viper.GetString("broadcast_pipeline")
+		if useV2Fallback("capture.broadcast.pipeline") {
+			s.BroadcastPipeline = viper.GetString("broadcast_pipeline")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_BROADCAST_PIPELINE' which is deprecated, please use 'NEKO_CAPTURE_BROADCAST_PIPELINE' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("broadcast_url") {
-		s.BroadcastUrl = viper.GetString("broadcast_url")
+		if useV2Fallback("capture.broadcast.url") {
+			s.BroadcastUrl = viper.GetString("broadcast_url")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_BROADCAST_URL' which is deprecated, please use 'NEKO_CAPTURE_BROADCAST_URL' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("broadcast_autostart") {
-		s.BroadcastAutostart = viper.GetBool("broadcast_autostart")
+		if useV2Fallback("capture.broadcast.autostart") {
+			s.BroadcastAutostart = viper.GetBool("broadcast_autostart")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_BROADCAST_AUTOSTART' which is deprecated, please use 'NEKO_CAPTURE_BROADCAST_AUTOSTART' instead")
 		deprecatedV2ConfigUsed = true
 	}
 
 	if deprecatedV2ConfigUsed {
-		log.Warn().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
+		log.Error().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
 	}
 }

server/internal/config/desktop.go

@@ -121,7 +121,7 @@ func (s *Desktop) SetV2() {
 			height, err2 := strconv.ParseInt(res[2], 10, 64)
 			rate, err3 := strconv.ParseInt(res[3], 10, 64)
 
-			if err1 == nil && err2 == nil && err3 == nil {
+			if err1 == nil && err2 == nil && err3 == nil && useV2Fallback("desktop.screen") {
 				s.ScreenSize.Width = int(width)
 				s.ScreenSize.Height = int(height)
 				s.ScreenSize.Rate = int16(rate)
@@ -132,6 +132,6 @@ func (s *Desktop) SetV2() {
 	}
 
 	if deprecatedV2ConfigUsed {
-		log.Warn().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
+		log.Error().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
 	}
 }

server/internal/config/member.go

@@ -269,22 +269,28 @@ func (s *Member) SetV2() {
 	deprecatedV2ConfigUsed := false
 
 	if viper.IsSet("password") || viper.IsSet("password_admin") {
-		s.Provider = "multiuser"
+		if useV2Fallback("member.provider") {
-		if userPassword := viper.GetString("password"); userPassword != "" {
+			s.Provider = "multiuser"
-			s.Multiuser.UserPassword = userPassword
-		} else {
-			s.Multiuser.UserPassword = "neko"
 		}
-		if adminPassword := viper.GetString("password_admin"); adminPassword != "" {
+		if viper.IsSet("password") && useV2Fallback("member.multiuser.user_password") {
-			s.Multiuser.AdminPassword = adminPassword
+			if userPassword := viper.GetString("password"); userPassword != "" {
-		} else {
+				s.Multiuser.UserPassword = userPassword
-			s.Multiuser.AdminPassword = "admin"
+			} else {
+				s.Multiuser.UserPassword = "neko"
+			}
+		}
+		if viper.IsSet("password_admin") && useV2Fallback("member.multiuser.admin_password") {
+			if adminPassword := viper.GetString("password_admin"); adminPassword != "" {
+				s.Multiuser.AdminPassword = adminPassword
+			} else {
+				s.Multiuser.AdminPassword = "admin"
+			}
 		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_PASSWORD' and 'NEKO_PASSWORD_ADMIN' which are deprecated, please use 'NEKO_MEMBER_MULTIUSER_USER_PASSWORD' and 'NEKO_MEMBER_MULTIUSER_ADMIN_PASSWORD' with 'NEKO_MEMBER_PROVIDER=multiuser' instead")
 		deprecatedV2ConfigUsed = true
 	}
 
 	if deprecatedV2ConfigUsed {
-		log.Warn().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
+		log.Error().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
 	}
 }

server/internal/config/root.go

@@ -4,6 +4,7 @@ import (
 	"os"
 	"path/filepath"
 	"runtime"
+	"slices"
 
 	"github.com/rs/zerolog"
 	"github.com/rs/zerolog/log"
@@ -11,6 +12,10 @@ import (
 	"github.com/spf13/viper"
 )
 
+func useV2Fallback(v3Keys ...string) bool {
+	return !slices.ContainsFunc(v3Keys, viper.IsSet)
+}
+
 type Root struct {
 	Config string
 
@@ -109,14 +114,16 @@ func (s *Root) Set() {
 
 func (s *Root) SetV2() {
 	if viper.IsSet("logs") {
-		if viper.GetBool("logs") {
+		if useV2Fallback("log.dir") {
-			logs := filepath.Join(".", "logs")
+			if viper.GetBool("logs") {
-			if runtime.GOOS == "linux" {
+				logs := filepath.Join(".", "logs")
-				logs = "/var/log/neko"
+				if runtime.GOOS == "linux" {
+					logs = "/var/log/neko"
+				}
+				s.LogDir = logs
+			} else {
+				s.LogDir = ""
 			}
-			s.LogDir = logs
-		} else {
-			s.LogDir = ""
 		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_LOGS' which is deprecated, please use 'NEKO_LOG_DIR=/path/to/logs' instead")
 	}

server/internal/config/server.go

@@ -130,37 +130,51 @@ func (s *Server) SetV2() {
 	deprecatedV2ConfigUsed := false
 
 	if viper.IsSet("cert") {
-		s.Cert = viper.GetString("cert")
+		if useV2Fallback("server.cert") {
+			s.Cert = viper.GetString("cert")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_CERT' which is deprecated, please use 'NEKO_SERVER_CERT' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("key") {
-		s.Key = viper.GetString("key")
+		if useV2Fallback("server.key") {
+			s.Key = viper.GetString("key")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_KEY' which is deprecated, please use 'NEKO_SERVER_KEY' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("bind") {
-		s.Bind = viper.GetString("bind")
+		if useV2Fallback("server.bind") {
+			s.Bind = viper.GetString("bind")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_BIND' which is deprecated, please use 'NEKO_SERVER_BIND' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("proxy") {
-		s.Proxy = viper.GetBool("proxy")
+		if useV2Fallback("server.proxy") {
+			s.Proxy = viper.GetBool("proxy")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_PROXY' which is deprecated, please use 'NEKO_SERVER_PROXY' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("static") {
-		s.Static = viper.GetString("static")
+		if useV2Fallback("server.static") {
+			s.Static = viper.GetString("static")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_STATIC' which is deprecated, please use 'NEKO_SERVER_STATIC' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("path_prefix") {
-		s.PathPrefix = path.Join("/", path.Clean(viper.GetString("path_prefix")))
+		if useV2Fallback("server.path_prefix") {
+			s.PathPrefix = path.Join("/", path.Clean(viper.GetString("path_prefix")))
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_PATH_PREFIX' which is deprecated, please use 'NEKO_SERVER_PATH_PREFIX' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("cors") {
-		s.CORS = viper.GetStringSlice("cors")
+		if useV2Fallback("server.cors") {
+			s.CORS = viper.GetStringSlice("cors")
+		}
 		if slices.Contains(s.CORS, "*") {
 			s.CORS = []string{"*"}
 			log.Warn().Msg("CORS is enabled for all origins, this is not recommended for production environments")
@@ -170,7 +184,7 @@ func (s *Server) SetV2() {
 	}
 
 	if deprecatedV2ConfigUsed {
-		log.Warn().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
+		log.Error().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
 	}
 }
 

server/internal/config/session.go

@@ -179,9 +179,13 @@ func (s *Session) SetV2() {
 			switch lock {
 			// TODO: file_transfer
 			case "control":
-				s.LockedControls = true
+				if useV2Fallback("session.locked_controls") {
+					s.LockedControls = true
+				}
 			case "login":
-				s.LockedLogins = true
+				if useV2Fallback("session.locked_logins") {
+					s.LockedLogins = true
+				}
 			}
 		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_LOCKS' which is deprecated, please use 'NEKO_SESSION_LOCKED_CONTROLS' and 'NEKO_SESSION_LOCKED_LOGINS' instead")
@@ -189,22 +193,28 @@ func (s *Session) SetV2() {
 	}
 
 	if viper.IsSet("implicit_control") {
-		s.ImplicitHosting = viper.GetBool("implicit_control")
+		if useV2Fallback("session.implicit_hosting") {
+			s.ImplicitHosting = viper.GetBool("implicit_control")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_IMPLICIT_CONTROL' which is deprecated, please use 'NEKO_SESSION_IMPLICIT_HOSTING' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("control_protection") {
-		s.ControlProtection = viper.GetBool("control_protection")
+		if useV2Fallback("session.control_protection") {
+			s.ControlProtection = viper.GetBool("control_protection")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_CONTROL_PROTECTION' which is deprecated, please use 'NEKO_SESSION_CONTROL_PROTECTION' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("heartbeat_interval") {
-		s.HeartbeatInterval = viper.GetInt("heartbeat_interval")
+		if useV2Fallback("session.heartbeat_interval") {
+			s.HeartbeatInterval = viper.GetInt("heartbeat_interval")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_HEARTBEAT_INTERVAL' which is deprecated, please use 'NEKO_SESSION_HEARTBEAT_INTERVAL' instead")
 		deprecatedV2ConfigUsed = true
 	}
 
 	if deprecatedV2ConfigUsed {
-		log.Warn().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
+		log.Error().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
 	}
 }

server/internal/config/webrtc.go

@@ -321,22 +321,30 @@ func (s *WebRTC) SetV2() {
 	deprecatedV2ConfigUsed := false
 
 	if viper.IsSet("nat1to1") {
-		s.NAT1To1IPs = viper.GetStringSlice("nat1to1")
+		if useV2Fallback("webrtc.nat1to1") {
+			s.NAT1To1IPs = viper.GetStringSlice("nat1to1")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_NAT1TO1' which is deprecated, please use 'NEKO_WEBRTC_NAT1TO1' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("tcpmux") {
-		s.TCPMux = viper.GetInt("tcpmux")
+		if useV2Fallback("webrtc.tcpmux") {
+			s.TCPMux = viper.GetInt("tcpmux")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_TCPMUX' which is deprecated, please use 'NEKO_WEBRTC_TCPMUX' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("udpmux") {
-		s.UDPMux = viper.GetInt("udpmux")
+		if useV2Fallback("webrtc.udpmux") {
+			s.UDPMux = viper.GetInt("udpmux")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_UDPMUX' which is deprecated, please use 'NEKO_WEBRTC_UDPMUX' instead")
 		deprecatedV2ConfigUsed = true
 	}
 	if viper.IsSet("icelite") {
-		s.ICELite = viper.GetBool("icelite")
+		if useV2Fallback("webrtc.icelite") {
+			s.ICELite = viper.GetBool("icelite")
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_ICELITE' which is deprecated, please use 'NEKO_WEBRTC_ICELITE' instead")
 		deprecatedV2ConfigUsed = true
 	}
@@ -350,24 +358,32 @@ func (s *WebRTC) SetV2() {
 				log.Panic().Err(err).Msg("failed to process iceservers")
 			}
 		}
-		s.ICEServersFrontend = iceServers
+		if useV2Fallback("webrtc.iceservers.frontend", "webrtc.iceservers") {
-		s.ICEServersBackend = iceServers
+			s.ICEServersFrontend = iceServers
+		}
+		if useV2Fallback("webrtc.iceservers.backend", "webrtc.iceservers") {
+			s.ICEServersBackend = iceServers
+		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_ICESERVERS' which is deprecated, please use 'NEKO_WEBRTC_ICESERVERS_FRONTEND' and/or 'NEKO_WEBRTC_ICESERVERS_BACKEND' instead")
 		deprecatedV2ConfigUsed = true
 	}
 
 	if viper.IsSet("iceserver") {
 		iceServerSlice := viper.GetStringSlice("iceserver")
-		if len(iceServerSlice) > 0 {
+		if len(iceServerSlice) > 0 && (useV2Fallback("webrtc.iceservers.frontend", "webrtc.iceservers") || useV2Fallback("webrtc.iceservers.backend", "webrtc.iceservers")) {
-			s.ICEServersFrontend = append(s.ICEServersFrontend, types.ICEServer{URLs: iceServerSlice})
+			if useV2Fallback("webrtc.iceservers.frontend", "webrtc.iceservers") {
-			s.ICEServersBackend = append(s.ICEServersBackend, types.ICEServer{URLs: iceServerSlice})
+				s.ICEServersFrontend = append(s.ICEServersFrontend, types.ICEServer{URLs: iceServerSlice})
+			}
+			if useV2Fallback("webrtc.iceservers.backend", "webrtc.iceservers") {
+				s.ICEServersBackend = append(s.ICEServersBackend, types.ICEServer{URLs: iceServerSlice})
+			}
 		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_ICESERVER' which is deprecated, please use 'NEKO_WEBRTC_ICESERVERS_FRONTEND' and/or 'NEKO_WEBRTC_ICESERVERS_BACKEND' instead")
 		deprecatedV2ConfigUsed = true
 	}
 
 	if viper.IsSet("ipfetch") {
-		if len(s.NAT1To1IPs) == 0 {
+		if len(s.NAT1To1IPs) == 0 && useV2Fallback("webrtc.nat1to1", "webrtc.ip_retrieval_url") {
 			ipfetch := viper.GetString("ipfetch")
 			ip, err := utils.HttpRequestGET(ipfetch)
 			if err != nil {
@@ -396,18 +412,20 @@ func (s *WebRTC) SetV2() {
 			}
 		}
 
-		if min > max {
+		if useV2Fallback("webrtc.epr") {
-			s.EphemeralMin = max
+			if min > max {
-			s.EphemeralMax = min
+				s.EphemeralMin = max
-		} else {
+				s.EphemeralMax = min
-			s.EphemeralMin = min
+			} else {
-			s.EphemeralMax = max
+				s.EphemeralMin = min
+				s.EphemeralMax = max
+			}
 		}
 		log.Warn().Msg("you are using v2 configuration 'NEKO_EPR' which is deprecated, please use 'NEKO_WEBRTC_EPR' instead")
 		deprecatedV2ConfigUsed = true
 	}
 
 	if deprecatedV2ConfigUsed {
-		log.Warn().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
+		log.Error().Msg("deprecated V2 configuration is in use; migrate to V3 configuration, see https://neko.m1k1o.net/docs/v3/migration-from-v2")
 	}
 }

webpage/docs/migration-from-v2/README.md

@@ -1,6 +1,6 @@
 # Migration from V2
 
-Neko v3 accepts many V2 configuration options as deprecated aliases, which are mapped to their V3 equivalents. When both forms are set, the V2 option takes precedence. The V2 API and client compatibility layer have been removed; clients must use the V3 API.
+Neko v3 accepts many V2 configuration options as deprecated aliases, which are mapped to their V3 equivalents. When both forms are set, the V3 option takes precedence. The V2 API and client compatibility layer have been removed; clients must use the V3 API.
 
 ## Docker Images {#docker}