# Latest **URL:** https://discuss.akka.io/latest.md [Latest](https://discuss.akka.io/latest.md) · [Categories](https://discuss.akka.io/categories.md) · [Tags](https://discuss.akka.io/tags.md) --- ## [OpenTelemetry Setup for the new Akka Java SDK](https://discuss.akka.io/t/opentelemetry-setup-for-the-new-akka-java-sdk/11663)
**Author:** [@theleoborges](https://discuss.akka.io/u/theleoborges)\ **Replies:** 9\ **Last updated:** [August 26, 2025, 9:31am UTC](https://discuss.akka.io/t/opentelemetry-setup-for-the-new-akka-java-sdk/11663 "2025-08-26T09:31:26Z")
As per the docs, here’s how I setup my SDK: akka.javasdk { agent { model-provider = openai openai { model-name = "gpt-4o-mini" api-key = ${?OPENAI\_API\_KEY} } } telemetry { tracing { … --- ## [A Conceptual Model of "Varying Inertia" (NKTg Law) — Could Akka Simulate Physical Dynamics?](https://discuss.akka.io/t/a-conceptual-model-of-varying-inertia-nktg-law-could-akka-simulate-physical-dynamics/11643)
**Author:** [@NKTgLaw](https://discuss.akka.io/u/NKTgLaw)\ **Replies:** 0\ **Last updated:** [August 14, 2025, 6:27am UTC](https://discuss.akka.io/t/a-conceptual-model-of-varying-inertia-nktg-law-could-akka-simulate-physical-dynamics/11643 "2025-08-14T06:27:45Z")
Hi everyone, I’d like to introduce a conceptual framework—the NKTg Law—that models how an object’s motion changes when mass varies over time. I’m curious if Akka (especially Akka Streams or typed actors) could be a good… --- ## [Partial Event Sourcing](https://discuss.akka.io/t/partial-event-sourcing/11634)
**Author:** [@tnichollcnc](https://discuss.akka.io/u/tnichollcnc)\ **Replies:** 0\ **Last updated:** [August 7, 2025, 3:17pm UTC](https://discuss.akka.io/t/partial-event-sourcing/11634 "2025-08-07T15:17:38Z")
Looking for some feedback on an idea that I’m calling “Partial Event Sourcing”. Suppose you have some complex state S built from a stream of events of type E1 or E2. E1 are regular, persisted events like we are familiar… --- ## [Reusability of Sources in Akka Streams](https://discuss.akka.io/t/reusability-of-sources-in-akka-streams/11532)
**Author:** [@kstokoz](https://discuss.akka.io/u/kstokoz)\ **Replies:** 2\ **Last updated:** [August 4, 2025, 8:33am UTC](https://discuss.akka.io/t/reusability-of-sources-in-akka-streams/11532 "2025-08-04T08:33:36Z")
The Akka Streams docs (Basics and working with Flows • Akka Documentation) mention that Sources can be reused (i.e., materialized multiple times), but I’ve seen cases where this doesn’t work — for example: Source.fromI… --- ## [TCP Connection between akka cluster nodes](https://discuss.akka.io/t/tcp-connection-between-akka-cluster-nodes/11488)
**Author:** [@vkp096](https://discuss.akka.io/u/vkp096)\ **Replies:** 2\ **Last updated:** [July 26, 2025, 11:37am UTC](https://discuss.akka.io/t/tcp-connection-between-akka-cluster-nodes/11488 "2025-07-26T11:37:41Z")
akkaVersion =‘2.6.21’ two hosts containing two akka jvms which are supposed to be clustering is not working due to the following error seen in seed-node error log running in linux machine: 2025-06-03 23:43:11,209 WARN… --- ## [Permanent deletion for withDeleteEventsOnSnapshot Criteria](https://discuss.akka.io/t/permanent-deletion-for-withdeleteeventsonsnapshot-criteria/5822)
**Author:** [@nur](https://discuss.akka.io/u/nur)\ **Replies:** 4\ **Last updated:** [July 24, 2025, 5:16am UTC](https://discuss.akka.io/t/permanent-deletion-for-withdeleteeventsonsnapshot-criteria/5822 "2025-07-24T05:16:41Z")
Hi, I want to permanently delete events in the persistence journal after a snapshot. I noticed that in the jdbc-journal they are only marked as deleted using withDeleteEventsOnSnapshot criteria. Will this ever be actuall… --- ## [Error downloading io.akka:sbt-paradox-akka NOT FOUND](https://discuss.akka.io/t/error-downloading-io-akka-sbt-paradox-akka-not-found/11536)
**Author:** [@python3js](https://discuss.akka.io/u/python3js)\ **Replies:** 1\ **Last updated:** [July 14, 2025, 3:19pm UTC](https://discuss.akka.io/t/error-downloading-io-akka-sbt-paradox-akka-not-found/11536 "2025-07-14T15:19:04Z")
I cloned the prjoect akka-persistence-dynamodb on my machine and created the file akka.sbt in the root directory: ThisBuild / resolvers += "akka-secure-mvn" at "https://repo.akka.io/\/secure" ThisBuild / re… --- ## [Are functional actors better than class based ones?](https://discuss.akka.io/t/are-functional-actors-better-than-class-based-ones/10814)
**Author:** [@AnonymousUser](https://discuss.akka.io/u/AnonymousUser)\ **Replies:** 1\ **Last updated:** [July 12, 2024, 5:21am UTC](https://discuss.akka.io/t/are-functional-actors-better-than-class-based-ones/10814 "2024-07-12T05:21:02Z")
Is there a performance difference or memory allocation consideration between class based actors and functional actors? This topic is based on a conversation between an anonymous user of Akka and our “Ask AI about Akka”… --- ## [Using implicit Ftps](https://discuss.akka.io/t/using-implicit-ftps/10591)
**Author:** [@sigurd](https://discuss.akka.io/u/sigurd)\ **Replies:** 3\ **Last updated:** [July 10, 2025, 10:50pm UTC](https://discuss.akka.io/t/using-implicit-ftps/10591 "2025-07-10T22:50:57Z")
Hey guys, I’m trying to use implicit FTPS. In the documentation, there is written Use it to configure any custom parameters the server may require, such as explicit or implicit data transfer encryption. FTP • Alpakk… --- ## [Offsetstore timeuuidoffset is not being updated](https://discuss.akka.io/t/offsetstore-timeuuidoffset-is-not-being-updated/11445)
**Author:** [@Gervais](https://discuss.akka.io/u/Gervais)\ **Replies:** 2\ **Last updated:** [July 4, 2025, 5:06pm UTC](https://discuss.akka.io/t/offsetstore-timeuuidoffset-is-not-being-updated/11445 "2025-07-04T17:06:01Z")
Hello Everyone, I have an issue since days and I don’t understand the root cause. I’m using Lagom and here are the relevant versions: Lagom 1.6.0 akka 2.6.9 akka-http 10.1.11 akka-persistence-cassandra 0.101 Events … --- ## [Is there any way to support Multiple TLS protocol versions to support backward compatability in akka via application.conf](https://discuss.akka.io/t/is-there-any-way-to-support-multiple-tls-protocol-versions-to-support-backward-compatability-in-akka-via-application-conf/11476)
**Author:** [@Ganeshram91](https://discuss.akka.io/u/Ganeshram91)\ **Replies:** 1\ **Last updated:** [June 3, 2025, 4:56pm UTC](https://discuss.akka.io/t/is-there-any-way-to-support-multiple-tls-protocol-versions-to-support-backward-compatability-in-akka-via-application-conf/11476 "2025-06-03T16:56:27Z")
Is there any way to support Multiple TLS protocol versions to support backward compatability in akka via application.conf for example both, \[“TLSv1.2”, “TLSv1.3”\] --- ## [Is it possible to check existence of persistent entity by it's id?](https://discuss.akka.io/t/is-it-possible-to-check-existence-of-persistent-entity-by-its-id/11521)
**Author:** [@shamoh](https://discuss.akka.io/u/shamoh)\ **Replies:** 1\ **Last updated:** [June 19, 2025, 6:51am UTC](https://discuss.akka.io/t/is-it-possible-to-check-existence-of-persistent-entity-by-its-id/11521 "2025-06-19T06:51:05Z")
Hello. I have a persistent entity, and in my use-case I need to handle a lot of requests with ID that do NOT represent an existing entity. There are millions of entities with unique ID. And just about 0.01 % of regular… --- ## [Continue buffering new messages when underlying persistence plugin throw ex](https://discuss.akka.io/t/continue-buffering-new-messages-when-underlying-persistence-plugin-throw-ex/11169)
**Author:** [@Charles](https://discuss.akka.io/u/Charles)\ **Replies:** 1\ **Last updated:** [January 7, 2025, 7:49am UTC](https://discuss.akka.io/t/continue-buffering-new-messages-when-underlying-persistence-plugin-throw-ex/11169 "2025-01-07T07:49:06Z")
I have some eventSourcedBehaviour setup as a cluster. And im uisng r2dbc plugin with postgres for both the journal and snapshot. when I simulate the failure of postgres(by switching it completely off), i first get this… --- ## [TLS connection not establishing after introducing new customsslengine class](https://discuss.akka.io/t/tls-connection-not-establishing-after-introducing-new-customsslengine-class/11501)
**Author:** [@Ganeshram91](https://discuss.akka.io/u/Ganeshram91)\ **Replies:** 0\ **Last updated:** [June 11, 2025, 7:00am UTC](https://discuss.akka.io/t/tls-connection-not-establishing-after-introducing-new-customsslengine-class/11501 "2025-06-11T07:00:15Z")
I have created new scala class for introducing customsslengine as below package akka.osgi; import akka.actor.ActorSystem import akka.event.{Logging, LoggingAdapter} import akka.remote.artery.tcp.ConfigSSLEngineProvid… --- ## [Which akka package to add in logback xml in the application to see TLS exceptions when TLS version mismatch found between provider and consumer](https://discuss.akka.io/t/which-akka-package-to-add-in-logback-xml-in-the-application-to-see-tls-exceptions-when-tls-version-mismatch-found-between-provider-and-consumer/11475)
**Author:** [@Ganeshram91](https://discuss.akka.io/u/Ganeshram91)\ **Replies:** 1\ **Last updated:** [June 3, 2025, 5:09pm UTC](https://discuss.akka.io/t/which-akka-package-to-add-in-logback-xml-in-the-application-to-see-tls-exceptions-when-tls-version-mismatch-found-between-provider-and-consumer/11475 "2025-06-03T17:09:19Z")
Which akka package to add in logback xml in the application to log and see TLS exceptions or TLS connection establishment failures when TLS version mismatch found between provider and consumer. we were using karaf envir… --- ## [Support for Multiple Protocols in AKKA Remote Artery SSL Configuration](https://discuss.akka.io/t/support-for-multiple-protocols-in-akka-remote-artery-ssl-configuration/11468)
**Author:** [@arun.t](https://discuss.akka.io/u/arun.t)\ **Replies:** 1\ **Last updated:** [May 28, 2025, 6:08am UTC](https://discuss.akka.io/t/support-for-multiple-protocols-in-akka-remote-artery-ssl-configuration/11468 "2025-05-28T06:08:15Z")
I’ve been reviewing the AKKA documentation, and it doesn’t explicitly state whether akka - remote.artery.ssl can support multiple protocols in its configuration. For instance, setting protocol = \["TLSv1.2", "TLSv1.3"\]. D… --- ## [Optional scalapb serialization binding breaks existing mapping](https://discuss.akka.io/t/optional-scalapb-serialization-binding-breaks-existing-mapping/11352)
**Author:** [@bekiroguz](https://discuss.akka.io/u/bekiroguz)\ **Replies:** 2\ **Last updated:** [March 26, 2025, 8:22am UTC](https://discuss.akka.io/t/optional-scalapb-serialization-binding-breaks-existing-mapping/11352 "2025-03-26T08:22:49Z")
Hi there, related to this feature in 2.9.0 release: feat: Optionally include serialization binding for ScalaPb by patriknw · Pull Request #32070 · akka/akka · GitHub I see that starting from akka 2.9.0, an optional ser… --- ## [How to detect that a consumer has disconnected from a stream](https://discuss.akka.io/t/how-to-detect-that-a-consumer-has-disconnected-from-a-stream/10701)
**Author:** [@sosborn-trumid](https://discuss.akka.io/u/sosborn-trumid)\ **Replies:** 1\ **Last updated:** [April 8, 2024, 8:46pm UTC](https://discuss.akka.io/t/how-to-detect-that-a-consumer-has-disconnected-from-a-stream/10701 "2024-04-08T20:46:18Z")
Given the following val ((queue, ks), source) = Source .queue\[MyThing\](queueSize, OverflowStrategy.dropHead) .viaMat(KillSwitches.single)(Keep.both) .preMaterialize() How can I detect … --- ## [Rolling Update with Remember Entites issue with newer Writer](https://discuss.akka.io/t/rolling-update-with-remember-entites-issue-with-newer-writer/11432)
**Author:** [@KDSBest](https://discuss.akka.io/u/KDSBest)\ **Replies:** 2\ **Last updated:** [May 7, 2025, 8:34am UTC](https://discuss.akka.io/t/rolling-update-with-remember-entites-issue-with-newer-writer/11432 "2025-05-07T08:34:42Z")
Hi everyone, if I perform a rolling Update with Remember-Entities on then the new node get plenty of errors from this line of code: val errMsg = s"Invalid replayed event \[sequenceNr=${r.persistent.sequenceNr}, writerUU… --- ## [Best way to pause an actor command and retry it without blocking the actor](https://discuss.akka.io/t/best-way-to-pause-an-actor-command-and-retry-it-without-blocking-the-actor/11039)
**Author:** [@ernleite](https://discuss.akka.io/u/ernleite)\ **Replies:** 1\ **Last updated:** [November 7, 2024, 12:48pm UTC](https://discuss.akka.io/t/best-way-to-pause-an-actor-command-and-retry-it-without-blocking-the-actor/11039 "2024-11-07T12:48:35Z")
hello, I am trying to find the best way to pause an actor command and retry it without blocking the actor itselt. Basically events are filling a hashtable and I need to wait until a specific index of my table is receive… --- ## [What is the purpose of GetLastOffset](https://discuss.akka.io/t/what-is-the-purpose-of-getlastoffset/11017)
**Author:** [@gmkumar2005](https://discuss.akka.io/u/gmkumar2005)\ **Replies:** 1\ **Last updated:** [October 28, 2024, 2:47pm UTC](https://discuss.akka.io/t/what-is-the-purpose-of-getlastoffset/11017 "2024-10-28T14:47:26Z")
akka-edge rust implementation has offset-store. It has GetLastOffset GetOffset and SaveOffset What is the purpose of GetLastOffset. How is it used to pause/resume or crash/resume scenarios? --- ## [Logging - Slf4jLogger started](https://discuss.akka.io/t/logging-slf4jlogger-started/10816)
**Author:** [@DaveO-Home](https://discuss.akka.io/u/DaveO-Home)\ **Replies:** 2\ **Last updated:** [July 31, 2024, 7:03pm UTC](https://discuss.akka.io/t/logging-slf4jlogger-started/10816 "2024-07-31T19:03:46Z")
Hi, I’m using scribe as my logger but I getting the following every time I log to the console: \[INFO\] \[akka.event.slf4j.Slf4jLogger\] - Slf4jLogger started Is there a way of silence this message? I do have log4j added … --- ## [Persistence failure when replaying events](https://discuss.akka.io/t/persistence-failure-when-replaying-events/1340)
**Author:** [@walrus](https://discuss.akka.io/u/walrus)\ **Replies:** 1\ **Last updated:** [June 20, 2018, 8:19pm UTC](https://discuss.akka.io/t/persistence-failure-when-replaying-events/1340 "2018-06-20T20:19:25Z")
Greetings, we’re developing an large akka-cluster system that uses akka-persistence-cassandra with journal events and generates a snapshot every 10 events. after several days of running, i started seeing frequent entrie… --- ## [Alpakka SE3 Connectors support with Ceph](https://discuss.akka.io/t/alpakka-se3-connectors-support-with-ceph/11045)
**Author:** [@Susmit07](https://discuss.akka.io/u/Susmit07)\ **Replies:** 1\ **Last updated:** [November 11, 2024, 6:24pm UTC](https://discuss.akka.io/t/alpakka-se3-connectors-support-with-ceph/11045 "2024-11-11T18:24:54Z")
Hello Fellow Engineers, I am having a basic question, currently we are using Alpakka S3 connectors with Cloudian S3, do we support Ceph as well Thanks, Susmit --- ## [Akka Memory Leak Issue](https://discuss.akka.io/t/akka-memory-leak-issue/11332)
**Author:** [@selim](https://discuss.akka.io/u/selim)\ **Replies:** 4\ **Last updated:** [March 26, 2025, 8:19pm UTC](https://discuss.akka.io/t/akka-memory-leak-issue/11332 "2025-03-26T20:19:09Z")
I’ve observed that the memory usage of the Akka Cluster nodes continuously increases, which eventually leads to pod restarts after a certain period. I can clearly see this trend while monitoring the memory usage. I’ve at… --- ## [Can we create actor from the context of shard actor?](https://discuss.akka.io/t/can-we-create-actor-from-the-context-of-shard-actor/10673)
**Author:** [@cpawali](https://discuss.akka.io/u/cpawali)\ **Replies:** 3\ **Last updated:** [March 20, 2024, 10:05am UTC](https://discuss.akka.io/t/can-we-create-actor-from-the-context-of-shard-actor/10673 "2024-03-20T10:05:56Z")
I want to understand can we create an actor from the context of shard actor(from inside shard actor) and delegate some work to it? What are the PROS and CONS of doing this? --- ## [Issue with EventProducerSource in app with many event sourced entitites](https://discuss.akka.io/t/issue-with-eventproducersource-in-app-with-many-event-sourced-entitites/11346)
**Author:** [@Mitep](https://discuss.akka.io/u/Mitep)\ **Replies:** 5\ **Last updated:** [March 24, 2025, 7:19am UTC](https://discuss.akka.io/t/issue-with-eventproducersource-in-app-with-many-event-sourced-entitites/11346 "2025-03-24T07:19:12Z")
Hello, I’m developing the Akka application using Event Sourcing in Cluster and Projections. I started the project using the examples given in Akka’s examples on GitHub. This is how the project looks: Event sourced Wo… --- ## [A problem with cinnamon instrumenting akka streams](https://discuss.akka.io/t/a-problem-with-cinnamon-instrumenting-akka-streams/11345)
**Author:** [@xeppaka](https://discuss.akka.io/u/xeppaka)\ **Replies:** 2\ **Last updated:** [March 18, 2025, 7:22am UTC](https://discuss.akka.io/t/a-problem-with-cinnamon-instrumenting-akka-streams/11345 "2025-03-18T07:22:50Z")
Hi, I’m using cinnamon for collecting metrics from akka streams and faced a weird behavior of the cinnamon library when RestartSource, RestartFlow or RestartSink is used. Basically the problem is that only RestartXXX ope… --- ## [My Bug while Using Multiple Cluster sharding with Akka Persistence](https://discuss.akka.io/t/my-bug-while-using-multiple-cluster-sharding-with-akka-persistence/7439)
**Author:** [@mockbean](https://discuss.akka.io/u/mockbean)\ **Replies:** 0\ **Last updated:** [November 5, 2020, 8:52pm UTC](https://discuss.akka.io/t/my-bug-while-using-multiple-cluster-sharding-with-akka-persistence/7439 "2020-11-05T20:52:04Z")
Hello, dear Akka gurus. I’m dealing with a bad bug that I hesitate if it is in my code or not. Consider I have three types of Entities (Actors :slight\_smile:). Type A: Akka’s Default ClusterSharding Type B & C: Kafka… --- ## [License key within Playframework](https://discuss.akka.io/t/license-key-within-playframework/11301)
**Author:** [@gervaisb](https://discuss.akka.io/u/gervaisb)\ **Replies:** 2\ **Last updated:** [February 20, 2025, 11:21pm UTC](https://discuss.akka.io/t/license-key-within-playframework/11301 "2025-02-20T23:21:04Z")
Hello there, We are (finally) migrating to Akka 2.10+ in our web application backed by Playframework. Unfortunately, we do have a strange behavior with the akka.license-key configuration. We can give it via the JVM op… [Next page](https://discuss.akka.io/latest.md?page=1)