My proxmox has many containers that must restart every time I reboot the host computer. Each is set to start on boot. There’s one container that starts, yet not all the services start. The mail container is the one in question. It is the first container that happens to start. Once it starts you can SSH in and reboot it in order to get the services to start.
The question is, why didn’t the services start? The container started. You could SSH into it which means it gets an IP address. Some services start but some don’t.
To keep the story short it looks like the cause is the boot time of the virtualized pfsense router. It took too much time for pfsense to start all the while the other containers and the VMs were also loading.
This took time to figure out. The first to load is the main container. Several of these containers are all starting in groups. Being the mail container was the first scheduled to load and pfsense was still starting some of the processes were trying to load but pfsense hadn’t even progressed to the point where it could issue IP addresses.
What we did was we set the startup delay of the pfsense VM. We set this to have a 120 second delay before the other containers and VMs would begin their start up sequence.
After testing it looks like this was enough of a delay to allow pfsense to get the DHCP and other related services up before Proxmox began loading the other containers and VMs.
Prior to establishing this delay, remember, above, I said it still issued the mail container an IP address. But this happened after and not during the startup. We simply delayed the start up to give it additional time to process pfsense.