OrientDB Server instance becomes unusable (no connection possible) after trying to execute task scheduled in the past

OrientDB Version: 3.2.43+

Java Version: Java 21 (not specific)

OS: Linux (not specific)

Expected behavior

Tasks scheduled in the past

Actual behavior

OrientDB Server instance becomes unusable (no connection possible) after trying to execute task scheduled in the past:

2025-09-10 09:20:00:001 INFO  Backup started FULL_BACKUP [OBackupTask]
2025-09-10 09:20:10:012 SEVER Exception in thread 'OrientDBEmbedded-1' [ScalingThreadPoolExecutor]
java.lang.IllegalArgumentException: Negative delay.
        at java.base/java.util.Timer.schedule(Timer.java:204)
        at com.orientechnologies.orient.core.Orient.scheduleTask(Orient.java:419)
        at com.orientechnologies.orient.core.Orient.scheduleTask(Orient.java:432)
        at com.orientechnologies.agent.services.backup.OBackupTask.schedule(OBackupTask.java:50)
        at com.orientechnologies.agent.services.backup.OBackupTask.onEvent(OBackupTask.java:116)
        at com.orientechnologies.agent.services.backup.strategy.OBackupStrategy.doBackup(OBackupStrategy.java:92)
        at com.orientechnologies.agent.services.backup.OBackupTask.lambda$null$0(OBackupTask.java:58)
        at java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:572)
        at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:317)
        at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1144)
        at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:642)
        at java.base/java.lang.Thread.run(Thread.java:1583)

OrientDB Server fails to start when a task is scheduled in the past with the following exception:

2025-09-10 09:35:32:585 SEVER Error during server execution [OServerMain$1]
java.lang.IllegalArgumentException: Negative delay.
        at java.base/java.util.Timer.schedule(Timer.java:204)
        at com.orientechnologies.orient.core.Orient.scheduleTask(Orient.java:419)
        at com.orientechnologies.orient.core.Orient.scheduleTask(Orient.java:432)
        at com.orientechnologies.agent.services.backup.OBackupTask.schedule(OBackupTask.java:50)
        at com.orientechnologies.agent.services.backup.OBackupTask.<init>(OBackupTask.java:42)
        at com.orientechnologies.agent.services.backup.OBackupService.initTasks(OBackupService.java:45)
        at com.orientechnologies.agent.services.backup.OBackupService.start(OBackupService.java:163)
        at com.orientechnologies.agent.OEnterpriseAgent.lambda$onAfterActivate$1(OEnterpriseAgent.java:317)
        at java.base/java.util.ArrayList.forEach(ArrayList.java:1596)
        at com.orientechnologies.agent.OEnterpriseAgent.onAfterActivate(OEnterpriseAgent.java:317)
        at com.orientechnologies.orient.server.OServer.activate(OServer.java:501)
        at com.orientechnologies.orient.server.OServerMain$1.run(OServerMain.java:49)

Workaround

Shutdown OrientDB server and remove OSystem database.

Steps to reproduce

1. Configure backup schedule
2. Wait until first execution
3. Wait until next execution
4. Restore backup from step 2 on a new instance

Start by tracing the stack from com.orientechnologies.orient.core.Orient.scheduleTask through OBackupTask.schedule and OBackupService.initTasks. Reproduce the backup and restore sequence with a past schedule, then verify that the server remains usable and can start without the Negative delay exception.