(updated again) [forge 39.0.8] FML requires an internet connection to launch

[Sumi]

I have internet issues, particularly that I need to unplug my ethernet to prevent lightning surges destroying all my network cards and router. As a result I've run into this problem. When I launch with an internet connection it goes through just fine in online mode. When I turn that connection off I get either
 

Quote

Error

Failed to run processor: java.net.UnknownHostException:launchermeta.mojang.com

See log for more details.

Or

Quote

Error

Failed to run processor: java.net.UnSocketException:Network is unreachable

See log for more details.

When I run the game with forge disabled in multimc, it loads up with no issues.

When I run it with no mods enabled, it still shows the same error.

When I run it with forge and a bad connection (on cellular) it hangs at DOWNLOAD_MOJMAPS despite being in offline mode. Then it times out with a network error which does not happen with vanilla.

When my connection is disabled after launching, nothing happens.

When launching in offline mode with a connection (enable connection after the launcher goes into offline mode) it works fine.

I'm guessing forge just doesn't have a check for offline mode and so requests MOJMAPS and other network reliant data without a failstate.

39.0.5, 39.0.6, 39.0.7 and 39.0.8 are all affected.

Log:

Spoiler

MultiMC version: 0.6.14-2998

Launched instance in offline mode

Minecraft folder is:
/home/user/.local/share/multimc/instances/1.18.1/.minecraft

Java path is:
/usr/bin/java

Checking Java version...
Java is version 17.0.1, using 64-bit architecture, from Private Build.

AMD Ryzen 7 4800H with Radeon Graphics
NVIDIA Corporation TU116M [GeForce GTX 1660 Ti Mobile] (rev a1)

Subsystem: ASUSTeK Computer Inc. TU116M [GeForce GTX 1660 Ti Mobile]

Kernel driver in use: nvidia

Advanced Micro Devices, Inc. [AMD/ATI] Renoir (rev c6)

Subsystem: ASUSTeK Computer Inc. Renoir

Kernel driver in use: amdgpu

OpenGL version string: 4.6.0 NVIDIA 460.91.03

Main Class:
  io.github.zekerzhayard.forgewrapper.installer.Main

Native path:
  /home/user/.local/share/multimc/instances/1.18.1/natives

Traits:
traits XR:Initial
traits FirstThreadOnMacOS

Libraries:
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-glfw/3.2.2/lwjgl-glfw-3.2.2.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-jemalloc/3.2.2/lwjgl-jemalloc-3.2.2.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-openal/3.2.2/lwjgl-openal-3.2.2.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-opengl/3.2.2/lwjgl-opengl-3.2.2.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-stb/3.2.2/lwjgl-stb-3.2.2.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-tinyfd/3.2.2/lwjgl-tinyfd-3.2.2.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl/3.2.2/lwjgl-3.2.2.jar
  /home/user/.local/share/multimc/libraries/com/mojang/blocklist/1.0.6/blocklist-1.0.6.jar
  /home/user/.local/share/multimc/libraries/com/mojang/patchy/2.1.6/patchy-2.1.6.jar
  /home/user/.local/share/multimc/libraries/com/github/oshi/oshi-core/5.8.2/oshi-core-5.8.2.jar
  /home/user/.local/share/multimc/libraries/net/java/dev/jna/jna/5.9.0/jna-5.9.0.jar
  /home/user/.local/share/multimc/libraries/net/java/dev/jna/jna-platform/5.9.0/jna-platform-5.9.0.jar
  /home/user/.local/share/multimc/libraries/org/slf4j/slf4j-api/1.8.0-beta4/slf4j-api-1.8.0-beta4.jar
  /home/user/.local/share/multimc/libraries/org/apache/logging/log4j/log4j-slf4j18-impl/2.16.0/log4j-slf4j18-impl-2.16.0.jar
  /home/user/.local/share/multimc/libraries/com/ibm/icu/icu4j/69.1/icu4j-69.1.jar
  /home/user/.local/share/multimc/libraries/com/mojang/javabridge/1.2.24/javabridge-1.2.24.jar
  /home/user/.local/share/multimc/libraries/net/sf/jopt-simple/jopt-simple/5.0.4/jopt-simple-5.0.4.jar
  /home/user/.local/share/multimc/libraries/io/netty/netty-all/4.1.68.Final/netty-all-4.1.68.Final.jar
  /home/user/.local/share/multimc/libraries/com/google/guava/failureaccess/1.0.1/failureaccess-1.0.1.jar
  /home/user/.local/share/multimc/libraries/com/google/guava/guava/31.0.1-jre/guava-31.0.1-jre.jar
  /home/user/.local/share/multimc/libraries/org/apache/commons/commons-lang3/3.12.0/commons-lang3-3.12.0.jar
  /home/user/.local/share/multimc/libraries/commons-io/commons-io/2.11.0/commons-io-2.11.0.jar
  /home/user/.local/share/multimc/libraries/commons-codec/commons-codec/1.15/commons-codec-1.15.jar
  /home/user/.local/share/multimc/libraries/com/mojang/brigadier/1.0.18/brigadier-1.0.18.jar
  /home/user/.local/share/multimc/libraries/com/mojang/datafixerupper/4.0.26/datafixerupper-4.0.26.jar
  /home/user/.local/share/multimc/libraries/com/google/code/gson/gson/2.8.8/gson-2.8.8.jar
  /home/user/.local/share/multimc/libraries/com/mojang/authlib/3.2.38/authlib-3.2.38.jar
  /home/user/.local/share/multimc/libraries/org/apache/commons/commons-compress/1.21/commons-compress-1.21.jar
  /home/user/.local/share/multimc/libraries/org/apache/httpcomponents/httpclient/4.5.13/httpclient-4.5.13.jar
  /home/user/.local/share/multimc/libraries/commons-logging/commons-logging/1.2/commons-logging-1.2.jar
  /home/user/.local/share/multimc/libraries/org/apache/httpcomponents/httpcore/4.4.14/httpcore-4.4.14.jar
  /home/user/.local/share/multimc/libraries/it/unimi/dsi/fastutil/8.5.6/fastutil-8.5.6.jar
  /home/user/.local/share/multimc/libraries/org/apache/logging/log4j/log4j-api/2.16.0/log4j-api-2.16.0.jar
  /home/user/.local/share/multimc/libraries/org/apache/logging/log4j/log4j-core/2.16.0/log4j-core-2.16.0.jar
  /home/user/.local/share/multimc/libraries/com/mojang/text2speech/1.11.3/text2speech-1.11.3.jar
  /home/user/.local/share/multimc/libraries/io/github/zekerzhayard/ForgeWrapper/mmc1/ForgeWrapper-mmc1.jar
  /home/user/.local/share/multimc/libraries/cpw/mods/securejarhandler/0.9.54/securejarhandler-0.9.54.jar
  /home/user/.local/share/multimc/libraries/org/ow2/asm/asm/9.1/asm-9.1.jar
  /home/user/.local/share/multimc/libraries/org/ow2/asm/asm-commons/9.1/asm-commons-9.1.jar
  /home/user/.local/share/multimc/libraries/org/ow2/asm/asm-tree/9.1/asm-tree-9.1.jar
  /home/user/.local/share/multimc/libraries/org/ow2/asm/asm-util/9.1/asm-util-9.1.jar
  /home/user/.local/share/multimc/libraries/org/ow2/asm/asm-analysis/9.1/asm-analysis-9.1.jar
  /home/user/.local/share/multimc/libraries/net/minecraftforge/accesstransformers/8.0.4/accesstransformers-8.0.4.jar
  /home/user/.local/share/multimc/libraries/org/antlr/antlr4-runtime/4.9.1/antlr4-runtime-4.9.1.jar
  /home/user/.local/share/multimc/libraries/net/minecraftforge/eventbus/5.0.3/eventbus-5.0.3.jar
  /home/user/.local/share/multimc/libraries/net/minecraftforge/forgespi/4.0.10/forgespi-4.0.10.jar
  /home/user/.local/share/multimc/libraries/net/minecraftforge/coremods/5.0.1/coremods-5.0.1.jar
  /home/user/.local/share/multimc/libraries/cpw/mods/modlauncher/9.0.7/modlauncher-9.0.7.jar
  /home/user/.local/share/multimc/libraries/net/minecraftforge/unsafe/0.2.0/unsafe-0.2.0.jar
  /home/user/.local/share/multimc/libraries/com/electronwill/night-config/core/3.6.4/core-3.6.4.jar
  /home/user/.local/share/multimc/libraries/com/electronwill/night-config/toml/3.6.4/toml-3.6.4.jar
  /home/user/.local/share/multimc/libraries/org/apache/maven/maven-artifact/3.6.3/maven-artifact-3.6.3.jar
  /home/user/.local/share/multimc/libraries/net/jodah/typetools/0.8.3/typetools-0.8.3.jar
  /home/user/.local/share/multimc/libraries/net/minecrell/terminalconsoleappender/1.2.0/terminalconsoleappender-1.2.0.jar
  /home/user/.local/share/multimc/libraries/org/jline/jline-reader/3.12.1/jline-reader-3.12.1.jar
  /home/user/.local/share/multimc/libraries/org/jline/jline-terminal/3.12.1/jline-terminal-3.12.1.jar
  /home/user/.local/share/multimc/libraries/org/spongepowered/mixin/0.8.5/mixin-0.8.5.jar
  /home/user/.local/share/multimc/libraries/org/openjdk/nashorn/nashorn-core/15.3/nashorn-core-15.3.jar
  /home/user/.local/share/multimc/libraries/cpw/mods/bootstraplauncher/0.1.17/bootstraplauncher-0.1.17.jar
  /home/user/.local/share/multimc/libraries/net/minecraftforge/fmlloader/1.18.1-39.0.8/fmlloader-1.18.1-39.0.8.jar
  /home/user/.local/share/multimc/libraries/com/mojang/minecraft/1.18.1/minecraft-1.18.1-client.jar

Native libraries:
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-glfw/3.2.2/lwjgl-glfw-3.2.2-natives-linux.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-jemalloc/3.2.2/lwjgl-jemalloc-3.2.2-natives-linux.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-openal/3.2.2/lwjgl-openal-3.2.2-natives-linux.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-opengl/3.2.2/lwjgl-opengl-3.2.2-natives-linux.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-stb/3.2.2/lwjgl-stb-3.2.2-natives-linux.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl-tinyfd/3.2.2/lwjgl-tinyfd-3.2.2-natives-linux.jar
  /home/user/.local/share/multimc/libraries/org/lwjgl/lwjgl/3.2.2/lwjgl-3.2.2-natives-linux.jar
  /home/user/.local/share/multimc/libraries/com/mojang/text2speech/1.11.3/text2speech-1.11.3-natives-linux.jar

Mods:
  [✔️] architectury-3.2.51
  [✔️] cloth-config-6.1.48-forge
  [✔️] GameMenuModOption-1.18-Forge-1.13
  [✔️] light-overlay-6.0.4-forge
  [❌] NotEnoughItems-1.12.2-2.4.3.245-universal.jar (disabled)
  [✔️] OptiFine_1.18.1_HD_U_H4
  [✔️] ShulkerTooltip-1.10
  [❌] Xaeros_Minimap_21.22.5_Forge_1.18.jar (disabled)
  [✔️] Xaeros_Minimap_21.22.6_Forge_1.18
  [✔️] XaerosWorldMap_1.18.8_Forge_1.18

Params:
  --username  --version MultiMC5 --gameDir /home/user/.local/share/multimc/instances/1.18.1/.minecraft --assetsDir /home/user/.local/share/multimc/assets --assetIndex 1.18 --uuid  --accessToken  --userType  --versionType release --launchTarget forgeclient --fml.forgeVersion 39.0.8 --fml.mcVersion 1.18.1 --fml.forgeGroup net.minecraftforge --fml.mcpVersion 20211210.034407

Window size: 854 x 480

Java Arguments:
[-Xms1024m, -Xmx4096m, -Duser.language=en]

Minecraft process ID: 11350

Using onesix launcher.

Missing: /home/user/.local/share/multimc/libraries/net/minecraft/client/1.18.1-20211210.034407/client-1.18.1-20211210.034407-unpacked.jar
Some extra libraries are missing! Running the installer to generate them now.
JVM info: Private Build - 17.0.1 - 17.0.1+12-Ubuntu-120.04
java.net.preferIPv4Stack=true
Created Temporary Directory: /tmp/forge_installer13049565701319295362
  Extracting: /data/client.lzma
Building Processors
===============================================================================
  MainClass: net.minecraftforge.installertools.ConsoleTool
  Classpath:
    /home/user/.local/share/multimc/libraries/net/minecraftforge/installertools/1.2.10/installertools-1.2.10.jar
    /home/user/.local/share/multimc/libraries/net/md-5/SpecialSource/1.10.0/SpecialSource-1.10.0.jar
    /home/user/.local/share/multimc/libraries/net/sf/jopt-simple/jopt-simple/5.0.4/jopt-simple-5.0.4.jar
    /home/user/.local/share/multimc/libraries/com/google/code/gson/gson/2.8.7/gson-2.8.7.jar
    /home/user/.local/share/multimc/libraries/de/siegmar/fastcsv/2.0.0/fastcsv-2.0.0.jar
    /home/user/.local/share/multimc/libraries/net/minecraftforge/srgutils/0.4.3/srgutils-0.4.3.jar
    /home/user/.local/share/multimc/libraries/org/ow2/asm/asm-commons/9.1/asm-commons-9.1.jar
    /home/user/.local/share/multimc/libraries/com/google/guava/guava/20.0/guava-20.0.jar
    /home/user/.local/share/multimc/libraries/com/opencsv/opencsv/4.4/opencsv-4.4.jar
    /home/user/.local/share/multimc/libraries/org/ow2/asm/asm-analysis/9.1/asm-analysis-9.1.jar
    /home/user/.local/share/multimc/libraries/org/ow2/asm/asm-tree/9.1/asm-tree-9.1.jar
    /home/user/.local/share/multimc/libraries/org/ow2/asm/asm/9.1/asm-9.1.jar
    /home/user/.local/share/multimc/libraries/org/apache/commons/commons-text/1.3/commons-text-1.3.jar
    /home/user/.local/share/multimc/libraries/org/apache/commons/commons-lang3/3.8.1/commons-lang3-3.8.1.jar
    /home/user/.local/share/multimc/libraries/commons-beanutils/commons-beanutils/1.9.3/commons-beanutils-1.9.3.jar
    /home/user/.local/share/multimc/libraries/org/apache/commons/commons-collections4/4.2/commons-collections4-4.2.jar
    /home/user/.local/share/multimc/libraries/commons-logging/commons-logging/1.2/commons-logging-1.2.jar
    /home/user/.local/share/multimc/libraries/commons-collections/commons-collections/3.2.2/commons-collections-3.2.2.jar
  Args: --task, MCP_DATA, --input, /home/user/.local/share/multimc/libraries/de/oceanlabs/mcp/mcp_config/1.18.1-20211210.034407/mcp_config-1.18.1-20211210.034407.zip, --output, /home/user/.local/share/multimc/libraries/de/oceanlabs/mcp/mcp_config/1.18.1-20211210.034407/mcp_config-1.18.1-20211210.034407-mappings.txt, --key, mappings
Task: MCP_DATA
Input:  /home/user/.local/share/multimc/libraries/de/oceanlabs/mcp/mcp_config/1.18.1-20211210.034407/mcp_config-1.18.1-20211210.034407.zip
Output: /home/user/.local/share/multimc/libraries/de/oceanlabs/mcp/mcp_config/1.18.1-20211210.034407/mcp_config-1.18.1-20211210.034407-mappings.txt
Key:    mappings
Extracting: config/joined.tsrg
===============================================================================
  MainClass: net.minecraftforge.installertools.ConsoleTool
  Classpath:
    /home/user/.local/share/multimc/libraries/net/minecraftforge/installertools/1.2.10/installertools-1.2.10.jar
    /home/user/.local/share/multimc/libraries/net/md-5/SpecialSource/1.10.0/SpecialSource-1.10.0.jar
    /home/user/.local/share/multimc/libraries/net/sf/jopt-simple/jopt-simple/5.0.4/jopt-simple-5.0.4.jar
    /home/user/.local/share/multimc/libraries/com/google/code/gson/gson/2.8.7/gson-2.8.7.jar
    /home/user/.local/share/multimc/libraries/de/siegmar/fastcsv/2.0.0/fastcsv-2.0.0.jar
    /home/user/.local/share/multimc/libraries/net/minecraftforge/srgutils/0.4.3/srgutils-0.4.3.jar
    /home/user/.local/share/multimc/libraries/org/ow2/asm/asm-commons/9.1/asm-commons-9.1.jar
    /home/user/.local/share/multimc/libraries/com/google/guava/guava/20.0/guava-20.0.jar
    /home/user/.local/share/multimc/libraries/com/opencsv/opencsv/4.4/opencsv-4.4.jar
    /home/user/.local/share/multimc/libraries/org/ow2/asm/asm-analysis/9.1/asm-analysis-9.1.jar
    /home/user/.local/share/multimc/libraries/org/ow2/asm/asm-tree/9.1/asm-tree-9.1.jar
    /home/user/.local/share/multimc/libraries/org/ow2/asm/asm/9.1/asm-9.1.jar
    /home/user/.local/share/multimc/libraries/org/apache/commons/commons-text/1.3/commons-text-1.3.jar
    /home/user/.local/share/multimc/libraries/org/apache/commons/commons-lang3/3.8.1/commons-lang3-3.8.1.jar
    /home/user/.local/share/multimc/libraries/commons-beanutils/commons-beanutils/1.9.3/commons-beanutils-1.9.3.jar
    /home/user/.local/share/multimc/libraries/org/apache/commons/commons-collections4/4.2/commons-collections4-4.2.jar
    /home/user/.local/share/multimc/libraries/commons-logging/commons-logging/1.2/commons-logging-1.2.jar
    /home/user/.local/share/multimc/libraries/commons-collections/commons-collections/3.2.2/commons-collections-3.2.2.jar
  Args: --task, DOWNLOAD_MOJMAPS, --version, 1.18.1, --side, client, --output, /home/user/.local/share/multimc/libraries/net/minecraft/client/1.18.1-20211210.034407/client-1.18.1-20211210.034407-mappings.txt
Task: DOWNLOAD_MOJMAPS
MC Version: 1.18.1
Side:       client
Output:     /home/user/.local/share/multimc/libraries/net/minecraft/client/1.18.1-20211210.034407/client-1.18.1-20211210.034407-mappings.txt
java.net.UnknownHostException: launchermeta.mojang.com
    at java.base/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:567)
    at java.base/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:327)
    at java.base/java.net.Socket.connect(Socket.java:633)
    at java.base/sun.security.ssl.SSLSocketImpl.connect(SSLSocketImpl.java:299)
    at java.base/sun.security.ssl.BaseSSLSocketImpl.connect(BaseSSLSocketImpl.java:174)
    at java.base/sun.net.NetworkClient.doConnect(NetworkClient.java:183)
    at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:498)
    at java.base/sun.net.www.http.HttpClient.openServer(HttpClient.java:603)
    at java.base/sun.net.www.protocol.https.HttpsClient.<init>(HttpsClient.java:266)
    at java.base/sun.net.www.protocol.https.HttpsClient.New(HttpsClient.java:380)
    at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.getNewHttpClient(AbstractDelegateHttpsURLConnection.java:189)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect0(HttpURLConnection.java:1242)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.plainConnect(HttpURLConnection.java:1128)
    at java.base/sun.net.www.protocol.https.AbstractDelegateHttpsURLConnection.connect(AbstractDelegateHttpsURLConnection.java:175)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream0(HttpURLConnection.java:1665)
    at java.base/sun.net.www.protocol.http.HttpURLConnection.getInputStream(HttpURLConnection.java:1589)
    at java.base/sun.net.www.protocol.https.HttpsURLConnectionImpl.getInputStream(HttpsURLConnectionImpl.java:224)
    at java.base/java.net.URL.openStream(URL.java:1161)
    at net.minecraftforge.installertools.DownloadMojmaps.process(DownloadMojmaps.java:65)
    at net.minecraftforge.installertools.ConsoleTool.main(ConsoleTool.java:55)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:568)
    at net.minecraftforge.installer.actions.PostProcessors.process(PostProcessors.java:226)
    at io.github.zekerzhayard.forgewrapper.installer.ClientInstall4MultiMC.run(ClientInstall4MultiMC.java:23)
    at io.github.zekerzhayard.forgewrapper.installer.util.InstallerUtil.runClientInstall(InstallerUtil.java:33)
    at io.github.zekerzhayard.forgewrapper.installer.Installer.install(Installer.java:21)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:568)
    at io.github.zekerzhayard.forgewrapper.installer.Main.main(Main.java:46)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    at java.base/java.lang.reflect.Method.invoke(Method.java:568)
    at org.multimc.onesix.OneSixLauncher.launchWithMainClass(OneSixLauncher.java:210)
    at org.multimc.onesix.OneSixLauncher.launch(OneSixLauncher.java:245)
    at org.multimc.EntryPoint.listen(EntryPoint.java:143)
    at org.multimc.EntryPoint.main(EntryPoint.java:34)
Failed to run processor: java.net.UnknownHostException:launchermeta.mojang.com
See log for more details.
Process exited with code 0.
Clipboard copy at: 23 Dec 2021 22:36:59 +1100

Any suggestions on how to solve this would be greatly appreciated, otherwise hopefully this will be a useful bug report. ;-;

Steps to hopefullly somewhat reliably reproduce:

1. use multimc to launch minecraft with forge 39.0.8, without a connection in offline mode
2. results in a network related error

I've tried installing forge on the vanilla launcher too, but that fails during installation which is a whole other topic. Otherwise I would have tested it there too.

Edited December 23, 2021 by Sumi
updated to latest release

[Sumi]

Still an issue in forge 39.0.7. Hangs on DOWNLOAD_MOJMAPS if on a slow connection, or shows UnknownHostException if disconnected altogether.