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Hello,
On Thu, 20 Jul 2000, Ted Pavlic wrote:
> Do you see any reason why enabling CIP->FWMARK for all cases would be a bad
> thing?
>
> That is, not only using case 2 for persistent FWMARK, but just whenever
> FWMARK was used. Personally, I cannot ever forsee a scenerio when a person
> would setup an FWMARK for load balancing and want each VIP associated with
> that FWMARK to act independently. <?>
Web cluster for independent domains (VIPs). FWMARK service
is used only to reduce the configuration.
>
> I've always thought that the scheduling algorithms should look directly at
> the real servers rather than the real server stats for each particular
> virtual server. That is, least connection scheduling would look at the total
> number of connections on a real server, not just the connections from that
> particular VIP. Round-robin would go round-robin from real server to real
> server based on the last connection from ANY VIP to the real servers...
> However, before FWMARK I realized that this would probably very difficult to
> do especially in cases where an LVS administrator was load balancing to a
> number of different real server clusters that may overlap.
This is a job for the user space tools: WRR scheduling
method + weights derived from the real server load. Yes, one real
server can be loaded from:
- many directors
- many virtual services
- other processes not part from the real service
In this case the director's opinion (for each virtual service)
about the real server load is wrong. The only way to handle such case
properly is to use WRR method. In the other cases WLC, LC and RR can do
their job.
>
> FWMARK, to me, just by causing all VIPs marked with a particular FWMARK to
> look like one big VIP makes it possible to do basically that which I just
> described. I don't see why anyone would not want such functionality with the
> FWMARK services. If one did want such functionality, he would probably
> partition the VIPs associated with his FWMARK into separate FWMARKs or even
> explicit VIP entries anyway.
Yes. IMO, this can be a problem only for the balancing but
I don't think so. The problems will come when one real server dies
and the client can't access any VIP part from the fwmark service for a
period of time.
Regards
--
Julian Anastasov <uli@xxxxxxxxxxxxxxxxxxxxxx>
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