Which external network domain names does Signal-cli connect to?

[shihab-geo]

On the server, there will be no open internet.
Currently I do have firewall access for https://signal.org, still getting this error while registering
Command error: Failed to register: java.net.SocketException: Network is unreachable (PushNetworkException)

[coderunner34-ahruphey]

I also experience this issue with version signal-cli 0.13.15.

What are the endpoint FQDN's ?

Errors:

`

./signal-cli -v -u +<My_GSM_Number> register

2025-06-01T13:14:20.730Z [main] DEBUG org.asamk.signal.App - Starting signal-cli 0.13.15
2025-06-01T13:14:20.930Z [main] DEBUG org.asamk.signal.util.IOUtils - XDG_DATA_HOME not set, falling back to home dir
2025-06-01T13:14:20.938Z [main] INFO com.zaxxer.hikari.HikariDataSource - HikariPool-1 - Starting...
2025-06-01T13:14:20.999Z [main] INFO com.zaxxer.hikari.pool.HikariPool - HikariPool-1 - Added connection org.sqlite.jdbc4.JDBC4Connection@3fb19f51
2025-06-01T13:14:21.000Z [main] INFO com.zaxxer.hikari.HikariDataSource - HikariPool-1 - Start completed.
2025-06-01T13:14:21.007Z [main] DEBUG o.a.s.m.util.NumberVerificationUtils - No registration session, creating new one.
2025-06-01T13:16:21.207Z [main] INFO com.zaxxer.hikari.HikariDataSource - HikariPool-1 - Shutdown initiated...
2025-06-01T13:16:21.207Z [main] INFO com.zaxxer.hikari.HikariDataSource - HikariPool-1 - Shutdown completed.
Failed to register: java.net.SocketTimeoutException: Connect timed out (PushNetworkException)
org.whispersystems.signalservice.api.push.exceptions.PushNetworkException: java.net.SocketTimeoutException: Connect timed out
at org.whispersystems.signalservice.internal.push.PushServiceSocket.getServiceConnection(PushServiceSocket.java:1296)
at org.whispersystems.signalservice.internal.push.PushServiceSocket.makeServiceRequest(PushServiceSocket.java:1202)
at org.whispersystems.signalservice.internal.push.PushServiceSocket.createVerificationSession(PushServiceSocket.java:238)
at org.whispersystems.signalservice.api.registration.RegistrationApi.createRegistrationSession$lambda$0(RegistrationApi.kt:33)
at org.whispersystems.signalservice.api.NetworkResult$Companion.fromFetch(NetworkResult.kt:53)
at org.whispersystems.signalservice.api.registration.RegistrationApi.createRegistrationSession(RegistrationApi.kt:32)
at org.asamk.signal.manager.util.NumberVerificationUtils.requestValidSession(NumberVerificationUtils.java:158)
at org.asamk.signal.manager.util.NumberVerificationUtils.getValidSession(NumberVerificationUtils.java:169)
at org.asamk.signal.manager.util.NumberVerificationUtils.handleVerificationSession(NumberVerificationUtils.java:41)
at org.asamk.signal.manager.internal.RegistrationManagerImpl.register(RegistrationManagerImpl.java:133)
at org.asamk.signal.commands.RegisterCommand.register(RegisterCommand.java:80)
at org.asamk.signal.commands.RegisterCommand.handleCommand(RegisterCommand.java:51)
at org.asamk.signal.commands.CommandHandler.handleRegistrationCommand(CommandHandler.java:33)
at org.asamk.signal.App.handleRegistrationCommand(App.java:268)
at org.asamk.signal.App.handleCommand(App.java:177)
at org.asamk.signal.App.init(App.java:147)
at org.asamk.signal.Main.main(Main.java:56)
at [email protected]/java.lang.invoke.LambdaForm$DMH/sa346b79c.invokeStaticInit(LambdaForm$DMH)
Caused by: java.net.SocketTimeoutException: Connect timed out
at [email protected]/sun.nio.ch.NioSocketImpl.timedFinishConnect(NioSocketImpl.java:546)
at [email protected]/sun.nio.ch.NioSocketImpl.connect(NioSocketImpl.java:592)
at [email protected]/java.net.SocksSocketImpl.connect(SocksSocketImpl.java:327)
at [email protected]/java.net.Socket.connect(Socket.java:751)
at okhttp3.internal.platform.Platform.connectSocket(Platform.kt:128)
at okhttp3.internal.connection.RealConnection.connectSocket(RealConnection.kt:295)
at okhttp3.internal.connection.RealConnection.connect(RealConnection.kt:207)
at okhttp3.internal.connection.ExchangeFinder.findConnection(ExchangeFinder.kt:226)
at okhttp3.internal.connection.ExchangeFinder.findHealthyConnection(ExchangeFinder.kt:106)
at okhttp3.internal.connection.ExchangeFinder.find(ExchangeFinder.kt:74)
at okhttp3.internal.connection.RealCall.initExchange$okhttp(RealCall.kt:255)
at okhttp3.internal.connection.ConnectInterceptor.intercept(ConnectInterceptor.kt:32)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.kt:109)
at okhttp3.internal.cache.CacheInterceptor.intercept(CacheInterceptor.kt:95)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.kt:109)
at okhttp3.internal.http.BridgeInterceptor.intercept(BridgeInterceptor.kt:83)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.kt:109)
at okhttp3.internal.http.RetryAndFollowUpInterceptor.intercept(RetryAndFollowUpInterceptor.kt:76)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.kt:109)
at org.asamk.signal.manager.config.ServiceConfig.lambda$getServiceEnvironmentConfig$0(ServiceConfig.java:41)
at okhttp3.internal.http.RealInterceptorChain.proceed(RealInterceptorChain.kt:109)
at okhttp3.internal.connection.RealCall.getResponseWithInterceptorChain$okhttp(RealCall.kt:201)
at okhttp3.internal.connection.RealCall.execute(RealCall.kt:154)
at org.whispersystems.signalservice.internal.push.PushServiceSocket.getServiceConnection(PushServiceSocket.java:1289)
... 17 more
Suppressed: java.net.SocketTimeoutException: Connect timed out
... 41 more
Suppressed: java.net.SocketTimeoutException: Connect timed out
... 41 more
Suppressed: java.net.SocketTimeoutException: Connect timed out
... 41 more

`