G
Guest
The Question:
A fundamental question about load balancing web traffic: Are 'sticky'
sessions unavoidable? Are there load balancing algorithms that will cope with
disproportionately large numbers of requests coming from a small group of IPs?
The Background:
We run a web portal hosted on our own web servers. In front of the web
servers we have a load balancer which distributes the traffic across all the
servers. We run our own large call centre, who also use elements of the
portal to advise potential customers. The call centre agents all sit on site
and hence all arrive at the load balancer with the same IP address.
The load balancer that we use interprets all the requests from the call
centre (plus all the other on-site employees, who also use the portal for
their work) as a single session, and hence sends all the requests to the same
web server.
The Result:
We have an evenly spread load over all but one of the web servers. The
remaining web server has an extremely high load in relation to the others,
sometimes as much as five times as high.
The Question again:
The load balancer manufacturer assures us that this is the expected
behaviour and that there is nothing that can be done on the load balancer to
avoid this situation. Is this believable? Are 'sticky' sessions unavoidable?
Are there load balancing algorithms that will cope with disproportionately
large numbers of requests coming from a small group of IPs?
Many thanks for any help or advice you can give.
Jon Little
A fundamental question about load balancing web traffic: Are 'sticky'
sessions unavoidable? Are there load balancing algorithms that will cope with
disproportionately large numbers of requests coming from a small group of IPs?
The Background:
We run a web portal hosted on our own web servers. In front of the web
servers we have a load balancer which distributes the traffic across all the
servers. We run our own large call centre, who also use elements of the
portal to advise potential customers. The call centre agents all sit on site
and hence all arrive at the load balancer with the same IP address.
The load balancer that we use interprets all the requests from the call
centre (plus all the other on-site employees, who also use the portal for
their work) as a single session, and hence sends all the requests to the same
web server.
The Result:
We have an evenly spread load over all but one of the web servers. The
remaining web server has an extremely high load in relation to the others,
sometimes as much as five times as high.
The Question again:
The load balancer manufacturer assures us that this is the expected
behaviour and that there is nothing that can be done on the load balancer to
avoid this situation. Is this believable? Are 'sticky' sessions unavoidable?
Are there load balancing algorithms that will cope with disproportionately
large numbers of requests coming from a small group of IPs?
Many thanks for any help or advice you can give.
Jon Little