Hello Shawn Thank you for your reply.
It is pretty much a verification of what we thought this end. Ill go back to the customer and let them know what Microsoft suggest is not possible. Andruw Smalley Loadbalancer.org Ltd. www.loadbalancer.org +1 888 867 9504 / +44 (0)330 380 1064 [email protected] Leave a Review | Deployment Guides | Blog On 14 February 2018 at 17:55, Shawn Heisey <[email protected]> wrote: > On 2/13/2018 7:49 AM, Andrew Smalley wrote: >> We have had a request and not sure if there is any way to implement this. >> >> Simply think of two real servers being loadbalanced. one fails all the >> connections are moved to the remaining server overloading it. >> >> What we want is for the traffic from the failed real server to be >> moved to the remaining real server without overloading it. IE Move a >> few connections at a time so the last server is not overloaded. > > The following is my understanding of how things work and what you have > said. If I have made any errors, I hope somebody will point them out. > > As far as I am aware, there is no way to "move" an existing connection > from one backend server to another. That would require special support > from both haproxy and the back end software. To my knowledge, that > capability does not exist. So existing connections at the moment of > failure are going to get closed down and the application (which may be a > browser) will need to try again. > > There isn't anything gradual about load shifting in the event of a > failure. Existing connections will be dropped and new connections will > be sent to whatever servers remain. > > When planning your capacity, it's prudent to take failures into account. > Failures *are* going to happen. They might be unplanned, such as a > motherboard failure or a datacenter outage, or they may be planned, so > you can upgrade software on the back end. > > If one server failing means that there is not enough remaining capacity > to handle the load, then you need more capacity, which may require more > servers. Ideally the remaining servers would handle the load without > users ever noticing any change, but in many environments it is > acceptable for performance to be a little worse until the failed server > is returned to service. > > Thanks, > Shawn >
