Server Load Balancer |
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High Availability |
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The high availability plays a key feature of the LB-8000, not only for LB-8000 itself, but also for the server farm or cluster's operating status. The key features are as follows: |
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Dual-path Heartbeat |
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Heartbeat signals between two LB-8000 are sent through both network and serial cable. Failover will not happen until backup fails to get the heartbeat signals from primary through both routes. This feature prevents unnecessary failover and avoids the problem that two LB-8000 are trying to become active (master) due to the network failure. |
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Bi-directional Stateful Failover |
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Real time synchronization between primary and backup LB-8000 ensures that two load balancers keep the same information about TCP connections and persistence. This state mirroring function, also called stateful failover, guarantees that no TCP connections or persistence information gets lost during failover. |
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Nice Fail Back |
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With Nice Fail Back, backup LB-8000 will become primary after failover happens. That way, even if original primary LB-8000 recovers afterwards, failover will not happen again. This feature can reduce the frequency of the failover and raise the availability of system. |
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Synchronization of Configurations and Logs |
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Bi-directional sync function makes sure that primary and backup LB-8000 always keep the same configurations and logs. This synchronization helps the backup LB-8000 take over the process / sessions of primary LB-8000 handles in microseconds where the remote users will never know the changes. |
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Server Health Check |
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The LB-8000 regularly checks the status of each server to make sure no traffic is forwarded to the malfunctioning ones. The health check includes ICMP check (Layer 3), port check (Layer 4) and content check (Layer 7). System admin can freely define which level of heath check to do. This shall protect network users from receiving incorrect packets or losing connection to the server because the session is sent to a server that has been already crashed. |
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Built for most IP-based Applications |
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LB-8000 is equipped with powerful PC system that helps handle all the requests from the Internet users to route to the arranged IP-based server behind the LB-8000, from WWW, FTP, to heavy traffic service like streaming servers. Three models help to optimize the usage of load sharing of your network, form NAT mode, direct-route mode and IP tunneling modes. The features are as below: |
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Load Balancing for most IP-based Applications |
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LB-8000 can load-balance most IP-based applications, such as web, email, FTP or streaming. You can also apply LB-8000 to other enterprise applications that have web-based GUI, including IBM WebSphere, Cold Fusion, BEA WebLogic Servers and Sun iPlanet Servers and so on. |
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Flexible Network Configurations |
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LB-8000 supports NAT (network address translation), direct routing and IP tunneling configurations. System admin will be able to choose the appropriete configuration according to the applications and environment. |
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Multiple Load Balancing Methods |
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LB-8000 provides both static and dynamic modes for load-balancing servers. Static modes contain round robin and weighted round robin. Dynamic modes include least connections and weighed least connections. |
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Active / Passive FTP Support |
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LB-8000 put special efforts on FTP application. No matter active or passive FTP, in NAT or direct routing mode, LB-8000 makes sure that FTP data session goes to the same real sever with FTP control session and the load can be still balanced. |
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ECOM Protocol |
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ECOM protocol makes sure the persistence is still valid when e-commerce visitors are going to SSL pages from normal web pages. |
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