# Can't connect graylog client to ElasticSearch cluster

**URL:** <https://discuss.elastic.co/t/cant-connect-graylog-client-to-elasticsearch-cluster/360992>\
**Category:** Elasticsearch\
**Created:** [June 6, 2024, 5:25pm UTC](https://discuss.elastic.co/t/cant-connect-graylog-client-to-elasticsearch-cluster/360992 "2024-06-06T17:25:27Z")\
**Posts on this page:** 2\
**Page:** 1

<div class="post-metadata">

**Author:** ![stecino](https://avatars.discourse-cdn.com/v4/letter/s/ea666f/32.png) [@stecino](https://discuss.elastic.co/u/stecino)\
**Post date:** [June 6, 2024, 5:25pm UTC](https://discuss.elastic.co/t/cant-connect-graylog-client-to-elasticsearch-cluster/360992/1 "2024-06-06T17:25:27Z")

</div>

Hello, I have reconfigured graylog client to connect from one Elasticsearch cluster to another. Both clusters are version 2.3.5. But when I try to restart the client, I am getting error

On master side

```auto
[WARN][discovery.zen] [herd-master2-blue] failed to validate incoming join request from node [{graylog-0063f44a-2ad6-4c04-89eb-7c6b2bb73fc3}{Dqm2JIMjRIC2in0tUPfW6Q}{xxx.xx.xx.xx}{xx.xx.xx.xxx:9350}{client=true, data=false, master=false}]

```

On client side

```auto
RemoteTransportException[[graylog-8165904c-fba8-4b6a-b2f0-f499d20bbd0c][xx.xxx.xxx.xx:9350][internal:discovery/zen/join/validate]]; nested: IllegalArgumentException[No custom metadata prototype registered for type [licenses], node like missing plugins]; ]

```

On the other cluster I have shield plugins installed, but disabled in config. Does it want me to remove the plugins? Or is it because client uuid still shows as part of the older cluster? If so does anyone know where on graylog client uuid information is stored please?

Thanks in advance

---

<div class="post-metadata">

**Author:** ![stephenb](https://sea2.discourse-cdn.com/elastic/user_avatar/discuss.elastic.co/stephenb/32/40856_2.png) [@stephenb](https://discuss.elastic.co/u/stephenb)\
**Post date:** [June 7, 2024, 5:45am UTC](https://discuss.elastic.co/t/cant-connect-graylog-client-to-elasticsearch-cluster/360992/2 "2024-06-07T05:45:29Z")

</div>

> [@stecino](#):
>
> Hello, I have reconfigured graylog client to connect from one Elasticsearch cluster to another. Both clusters are version 2.3.5.

> [@stecino](#):
>
> On the other cluster I have shield plugins installed, but disabled in config. Does it want me to remove the plugins?

Hi @stecino

Apologies... I doubt we are going to be able to help much

We don't support gray log here... perhaps someone may know something but not really a topic here.

Elasticsearch 2.3.5 that is like 8+ years old, doubt there is anyone here that has run that recently.

We don't support Shield Plugin either.. .

I think you need to go to the gray log forum...