# Kong not starting due to unknown error
**URL:** https://discuss.konghq.com/t/kong-not-starting-due-to-unknown-error/3406
**Category:** Questions
**Created:** [April 28, 2019, 9:03am UTC](https://discuss.konghq.com/t/kong-not-starting-due-to-unknown-error/3406 "2019-04-28T09:03:56Z")
**Posts on this page:** 4
**Page:** 1
### Author:  [@nix12](https://discuss.konghq.com/u/nix12)
#### Post date: [April 28, 2019, 9:03am UTC](https://discuss.konghq.com/t/kong-not-starting-due-to-unknown-error/3406/1 "2019-04-28T09:03:56Z")
I working on setting up kong version 1.1.2 from source, but ran into this error when I went to start kong:
```
Error: /usr/local/share/lua/5.1/kong/cmd/start.lua:50: nginx: [error] init_by_lua error: /usr/local/share/lua/5.1/kong/init.lua:402: error loading plugin schemas: on plugin 'datadog': [postgres] schema violation (fields.2: {
fields = {
[4] = {
default = "error in schema prevents from validating this field"
}
}
}); on plugin 'prometheus': failed converting legacy schema for prometheus: [postgres] schema violation (fields.1: {
fields = {
[2] = {
default = {
"expected a string",
"expected a string",
"expected a string",
"expected a string",
"expected a string",
"expected a string",
"expected a string",
"expected a string"
}
}
}
}); on plugin 'statsd': [postgres] schema violation (fields.2: {
fields = {
[4] = {
default = "error in schema prevents from validating this field"
}
}
})
stack traceback:
[C]: in function 'assert'
/usr/local/share/lua/5.1/kong/init.lua:402: in function 'init'
init_by_lua:3: in main chunk
Run with --v (verbose) or --vv (debug) for more details
```
I’ve tried to handle it on my own but failed miserably. I can’t quite understand what the error output is saying and I know next to nothing about lua. Can anyone point me in the right direction of how to fix this?
---
### Author:  [@hutchic](https://discuss.konghq.com/u/hutchic)
#### Post date: [April 28, 2019, 9:24pm UTC](https://discuss.konghq.com/t/kong-not-starting-due-to-unknown-error/3406/2 "2019-04-28T21:24:54Z")
Have you ran the Kong migrations already? Is this upgrading an existing Kong installation?
FWIW there’s a docker based development environment if that works for your needs: [https://github.com/Kong/kong-build-tools#developing-kong](https://github.com/Kong/kong-build-tools#developing-kong)
---
### Author:  [@nix12](https://discuss.konghq.com/u/nix12)
#### Post date: [April 28, 2019, 9:40pm UTC](https://discuss.konghq.com/t/kong-not-starting-due-to-unknown-error/3406/3 "2019-04-28T21:40:03Z")
Yes, I have ran the migrations, in fact, I have reset migrations several times with no changes to the error messages. As for the existing installation, this is not an upgrade, but a brand new installation. And for docker, I not knowledgeable on it. Should I give docker a try? And can it run on my local system?
---
### Author:  [@mgkong](https://discuss.konghq.com/u/mgkong)
#### Post date: [April 30, 2019, 2:31pm UTC](https://discuss.konghq.com/t/kong-not-starting-due-to-unknown-error/3406/4 "2019-04-30T14:31:05Z")
I would recommend starting Kong with --v (verbose) flag - it provides plenty of helpful messages/values of config parameters. Also, you can try re-installing PostgresSQL/kong db from scratch, run migrations and then start Kong with verbose flag.