Guido, I think you intended that message for me, not Brian. Thanks much for the feedback. I have been reading about Kubernetes, but I got discouraged when I saw that they dropped Docker support, since Docker seems to be the most popular containeriziation technology. Also, most of the Kubernetes tutorials I saw on YouTube seem to approach it as a dev platform, and we're not developers.
-Eric > -----Original Message----- > From: Guido Jäkel <g.jae...@dnb.de> > Sent: Monday, June 28, 2021 2:43 PM > To: Brian Wolfe <wolfebrian2...@gmail.com> > Cc: Tomcat Users List <us...@tomcat.apachre.org> > Subject: Re: 500 instances of tomcat on the same server > > Dear Brian, > > please take the time to read about Linux Kernel namespaces as the technical > base of containers. It's like two viewpoints to one thing. Take the network > namespace as an example: From the conceptual point of view it looks like > you have N indipended, functional identical "IP Stacks". But from the > technical point of view, it's just the "well known" single instance just with > an > additional field at all items that need this (packets, routing tables, ...) > to take > a tag value that identify the namespace instance. > > You may use namespaces with the raw tools like enterns or with LXC or > Dockers. During runtime of a started container, there's nothing more you > have to trust but the kernel because for the basics, there's no need of > additional userland processes to keep a container running. > > To run an application in a "container", you start it with a bunch of > instances of > this namespaces, at least the process namespace. You'll probably take the > same name for the technical namespace instances - from the conceptual > point of view this is the name of the container. > > Most will start something like the init binary located in a directory tree of > a > small Linux distribution userland. This may "boot" common services and the > result may act like an "indipended platfrom". But you may also launch just > single high-level applications like a JVM running a Tomcat. > > That's very close to your architecture, but much more easy to handle. For the > network stack e.g. you may use the same ports for listeners and have the full > range of ports available for connections in each namespace. There are > different ways available to route the traffic, but in any case you may use > individual IPs in each namespace. > > greetings > > Guido > > On 2021-06-28 19:22, Brian Wolfe wrote: > > Generally, I'd agree too. We are considering using containers, but I'm > > not yet sure what that buys us in terms of stability. > > --------------------------------------------------------------------- > To unsubscribe, e-mail: users-unsubscr...@tomcat.apache.org > For additional commands, e-mail: users-h...@tomcat.apache.org Disclaimer : This email and any files transmitted with it are confidential and intended solely for intended recipients. If you are not the named addressee you should not disseminate, distribute, copy or alter this email. Any views or opinions presented in this email are solely those of the author and might not represent those of Physician Select Management. Warning: Although Physician Select Management has taken reasonable precautions to ensure no viruses are present in this email, the company cannot accept responsibility for any loss or damage arising from the use of this email or attachments.