What is session affinity in a load balancer?

What is session affinity in a load balancer?

Session affinity is a feature available on load balancers that allows all subsequent traffic and requests from an initial client session to be passed to the same server in the pool. Session affinity is also referred to as session persistence, server affinity, server persistence, or server sticky.

Does Network Load Balancer support sticky sessions?

Sticky sessions are available for AWS Network Load Balancers. You simply set the switch on the target group properties. NLBs use IP addresses to control the stickiness. This means that if you have a lot of users with the same IP (behind a NAT for example) then then will all hit the same server.

How do you handle sessions in load balancer?

This is where the concept of “Sticky Sessions” or “Session Affinity” comes into play. You can configure many load balancers to route user sessions to the same machine. Another approach would be to maintain session information in a datastore accessible by both machines behind the load balancer.

What is IP address affinity?

Destination address affinity persistence , also known as sticky persistence, directs requests for a certain destination IP address to the same server, regardless of which client made the request.

Why do we need sticky session?

This is mainly used to ensure that a in-proc session is not lost as a result of requests for a session being routed to different servers. Since requests for a user are always routed to the same machine that first served the request for that session, sticky sessions can cause uneven load distribution across servers.

What is a session affinity?

Session affinity overrides the load-balancing algorithm by directing all requests in a session to a specific application server. Session affinity uses cookies to track session information and, potentially, to maintain login credentials.

What is client affinity?

Client affinity is defined between a client connection and a data source. When client affinity is defined, requests from a specified client connection are distributed to a specified data source in a data source pool.

How does client affinity help in network load balancing?

Sessions help to maintain user related variables and by maintaining the state of sessions, the application can ensure the user can complete a set of actions, like online shopping using a shopping cart application. Client affinity can be configured in Network Load Balancing (NLB) which helps in maintaining application sessions.

How does Network Load Balancing ( NLB ) work?

• None: Multiple requests from the same client are not redirected to the same server by Network Load Balancing (NLB) • Single: Multiple requests from the same client IP address should be redirected to the same server by Network Load Balancing (NLB)

How is Class C used in network load balancing?

• Class C: Multiple requests from the same Class C address range are redirected to the same server by Network Load Balancing (NLB). Class C affinity is useful for clients that use multiple proxy servers to access the cluster. The three filtering modes available are

What are the filtering modes in network load balancing?

The three filtering modes available are • Disabled: No filtering. • Single Host: Direct traffic to a single host. • Multiple Hosts: Distribute traffic between the Network Load Balancing (NLB) cluster servers. Do you have any suggestions? Please let us know!