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Plesk and load balancer

AndorA

Basic Pleskian
Hi,

I am running Plesk behind a load balancer, which creates a bit of a chatch 22. Of course this is a bit of an advanced configuration that few people would use, but it seems to me like the issue I have is very solvable. Just a small change would make Plesk suitable for a load balanced setup.

If someone knows a workaround in the current way Plesk works, of course I'd love to hear it, too!

First some facts I believe are true about Plesk, but please correct me if I'm wrong. A change in any of this would offer a solution to my problem:

1 In Plesk, a domain is always connected to just one IP.
2 If you change this IP to a wildcard in IIS for the http traffic (i.e., "all IPs should load this site"), Plesk changes it back to this one IP at set times, effectively blocking other IPs from loading the site.
3 You can change the address of the FTP server in Plesk DNS, but you cannot change the IP address in the FTP configuration of Plesk. This always needs to be this same one IP that your server is hosted on.
4 You cannot create FTP accounts outside of Plesk, that allow you to manage directories (vhosts) managed by Plesk. If it's not through the Plesk based account, you simply cannot get FTP access on a Plesk server.

Now, here is the issue. I have some sites on my Plesk server that at times have a lot of traffic. For those times, I run a separate (cloud) instance running just the site. That works perfectly well. I have a load balancer in between, so I can set to send the traffic either to my original Plesk server (the default), but at times of high traffic to one or more seperate servers just to catch this http traffic. It works perfectly fine, except Plesk actively tries to disturb my peace and happiness :) The thing is that I now deal with 3 IP addresses:

1. The original Plesk server's external IP, that I can use to connect to the server from outside
2. The original Plesk server's internal IP, that I can use to connect to the server from the internal network (i.e. the load balancer)
3. The IP of the load balancer

- In the DNS of my domain, I direct all http traffic to my load balancer. Works wonderfully.
- My load balancer then sends traffic back to the server through my internal IP, but only if in IIS my internal IP is set as the binding, which means this needs to be the IP selected for the subscription in Plesk, otherwise Plesks starts sabotaging.
- I can set the original servers' IP in the DNS through Plesk as the FTP address for the site, but since my site is now hosted on an internal IP, Plesk configures the server so that FTP is only accessible from that internal IP. This means that using a load balancer makes it impossible to use FTP anymore. It would work, if Plesk only allowed access over another IP than which the subscription is configured on.

There would be two solutions which I think would solve the whole issue (but I might be mistaken):
1. Allow the user to select a different IP for FTP. IN the FTP settings the IP is displayed, but it cannot be changed from internal to external IP.
2. Give an option to allow the administrator to prevent certain manual settings in IIS to be overwritten by Plesk.
3 (probably the best): allow multiple or even wildcard IP addresses to be selected in Plesk for use with a subscription.

If anyone else is using Plesk on load balanced sites or needs wildcard IPs for another reason, please second this feature request :)

Andor
 
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