# Can't run jruby commands on Logstash 8

**URL:** <https://discuss.elastic.co/t/cant-run-jruby-commands-on-logstash-8/371769>\
**Category:** Logstash\
**Created:** [December 10, 2024, 2:26pm UTC](https://discuss.elastic.co/t/cant-run-jruby-commands-on-logstash-8/371769 "2024-12-10T14:26:19Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![mcairney](https://avatars.discourse-cdn.com/v4/letter/m/ce7236/32.png) [@mcairney](https://discuss.elastic.co/u/mcairney)\
**Post date:** [December 10, 2024, 2:26pm UTC](https://discuss.elastic.co/t/cant-run-jruby-commands-on-logstash-8/371769/1 "2024-12-10T14:26:19Z")

</div>

Hi,  
We're looking to upgrade our ELK stack from 7.17 to 8.16 however I've discovered an issue with the jruby command throwing an error on 8.16 which means we can't build and install logstash plugins.

e.g.

```auto
# /usr/share/logstash/vendor/jruby/bin/jruby
Error: No such file or directory: 
/usr/share/logstash/vendor/jruby/bin/jruby: line 729: exec: : not found

```

While it behaves as expected on logstash 7.17.

I notice the breaking changes mention removing the Ruby execution engine, is this related?

If I compare The shell on V.8:

```auto
if $use_exec; then
    exec "$@"
else
    "$@"

```

With V7:

```auto
if $use_exec; then
  exec "${jvm_command[@]}"
else
  "${jvm_command[@]}"

```

Again, does this need tweaked on V8? Note this is a fresh install of logstash on a brand new Dev VM- I haven't configured any external JDKs or config.