1. What is the session remains?
Refers to a mechanism for holding the session on the server load balancing can be identified relevance of the interaction process between the client and the server, the same client session request is forwarded to the same backend server process.
2. The session held type
(1) four services (TCP protocol), the load balancing system is based on the source IP address of the session holder.
The server load balancing the access request source IP address as the basis for judging the associated session, all access requests from the same IP address in load balancing will be forwarded to the same server.
(2) seven-layer services (HTTP / HTTPS protocol), load balancing systems is to keep the cookie-based sessions. Use implants and rewrite cookie cookie to keep the conversation.
Implant cookie
Specifies the expiration time of the cookie. When the client first visit, load balancing service in the HTTP response message. The SERVERID, the next client to carry this cookie to access, load balancing service requests will be recorded on the orientation before it forwarded to the backend server.
Rewrite cookie
Specifies the HTTP response packet insertion of cookie. The need to maintain the expiration time of the cookie and the survival time on the back-end server. Load Balancing Service found that users customize the cookie, the cookie will overwrite the original, the next client to carry a new cookie access, load balancing service requests will be recorded on the orientation before forwarded to the backend server.