Containerize dovecot?

[Jeremiah C. Foster]

On 8/24/21 6:46 PM, William Edwards wrote:
> I think the general concensus is that containerisation isn't always 
> better than 'normal' VMs. 'Easy deployment & scaling' is also perfectly 
> possible without containers.

Without a doubt VMs are a good solution. Containers use some of the same 
technology however and since they're based on the Linux kernel API they 
can do it with a bit more performance (as opposed to emulating 
hardware). While the performance hit for a VM is small, most of the 
folks who use containers are trying to squeeze as many apps in a 
"multi-tenant" host which means every CPU cycle matters.

Also, with recent CGROUPS 2 changes there's the ability to nest containers.

I think overall containers offer a "capability based" paradigm while VMs 
offer an emulation paradigm. In theory the capability based paradigm 
ought to be easier to use and more flexible so it's reasonable that 
folks want to use it for things like Dovecot.

> MRob schreef op 2021-08-25 00:01:
>> Thank to other responses with links that i'll learning from! Thanks
>> you very much
>>
>> On 2021-08-24 00:35, Marc wrote:
>>> What are you trying to achieve with containerizing?
>>
>> hmm, easy deployment & scaling? also reslient against hardware 
>> crashes, etc.
>>
>>> You have to take into account that your
>>> storage is persistant,

Persistent storage is definitely something to think about and plan for 
but most containerization solutions offer easy ways to mount persistent 
storage into containers. This can be an advantage, your business logic 
can run in the container to which you ascribe a certain amount of CPU 
per your needs and your persistent data can live on the host file system.

>> Have you see what challenge this poses? Love to hear your opinion
>> about it. Maybe this is where using object-storage backend becomes
>> more powerful solution?
>>
>>> you have to take into account getting something
>>> like proxy to redirect traffic etc etc.

Indeed, ingress and egress as well as networking become more complex.

>> Yes I thought also proxy/director also become containerized. You said
>> this for teaching a certain point?
>>
>>> If you want to
>>> deploy the container on a orchestrator so it is going to be
>>> (re)started on a random hosts.
>>
>> you mention so because all hosts must be connected to same storage?
>>
>>> I managed to get this to work
>>> via alpine linux (nice small), but I think I am going back to vm.
>>
>> what reasons? what kind of vm do you use?
>>
>>
>>>>
>>>> Hello, anyone here has containerized dovecot? Can I ask general advice
>>>> and experience please? are there any recommended articles/tutorial for
>>>> containerize deploymnt and auto-scaling? Thank you.

Cheers,

Jeremiah