mwelsch

As mentioned in Issue #165 : If you are using the Toolkit check [manually-setting-up-mongodb-as-a-replica-set](https://github.com/overleaf/overleaf/wiki/Release-Notes--4.x.x#manually-setting-up-mongodb-as-a-replica-set) -> you need to run `docker-compose exec -it mongo mongo` and then the given command to...

So the reason why overleaf is not starting is this line of your log ``` Cannot connect to mongodb ``` I ran into this issue while upgrading the version, maybe...

What does your network setup look like? (You specified [external](https://docs.docker.com/compose/compose-file/06-networks/#external) and a [name](https://docs.docker.com/compose/compose-file/06-networks/#name) in the network area and assigned a dedicated [ipv4_adress](https://docs.docker.com/compose/compose-file/05-services/#ipv4_address-ipv6_address); additionally you [linked](https://docs.docker.com/compose/compose-file/05-services/#links) sharelatex to the other containers....

https://github.com/overleaf/overleaf/wiki/Quick-Start-Guide#latex-environment