CCNP Certification / BCMSN Exam Tutorial: Server Load Balancing (SLB)
Any time you’re working on your BCMSN Examination with your way to CCNP certification, you’ll browse at duration about how Cisco routers and multilayer switches can work to deliver router redundancy – but there’s One more useful assistance, Server Load Balancing, that does the identical for servers. Even though HSRP, VRRP, and CLBP all characterize multiple physical routers to hosts as only one Digital router, SLB represents numerous Actual physical servers to hosts as just one Digital server.
In the next illustration, 3 Actual physical servers have been positioned into the SRB team ServFarm. They’re represented into the hosts given that the Digital server 210.one.1.fourteen.
The hosts will look for to talk to the server at 210.1.1.fourteen, not being aware of that they’re really communicating Using the routers in ServFarm. This allows brief cutover if among the list of Actual physical servers goes down, in addition to serves to hide the particular IP addresses in the servers in ServFarm.
The fundamental operations of SLB includes producing the server farm, followed by producing the Digital server. We’ll very first incorporate 210.one.one.11 to your server farm:
MLS(config)# ip slb serverfarm ServFarm
MLS(config-slb-sfarm)# real 210.one.1.eleven
MLS(config-slb-genuine)# inservice
The main command results in the server farm, with the real command specifying the IP tackle of the real server. The inservice command is required by SLB to think about the server as Prepared to deal with the server farm’s workload. The real and inservice instructions needs to be recurring for every server within the server farm.
To produce the virtual server:
MLS(config)# ip slb vserver VIRTUAL_SERVER
MLS(config-slb-vserver)# serverfarm ServFarm
MLS(config-slb-vserver)# virtual 210.1.one.14
MLS(config-slb-vserver)# inservice
With the prime down, the vserver was named VIRTUAL_SERVER, which represents the server farm ServFarm. The virtual server is assigned the IP tackle 210.1.one.14, and connections are allowed once the inservice command is utilized.
You may also want to regulate which of one's community hosts can connect with the Digital server. If hosts or subnets are named Along with the consumer command, those would be the only clients that could hook up with the virtual server. Take note that this command utilizes wildcard masks. The next configuration would let only the hosts within the subnet 210.one.one.0 /24 to connect to the virtual server.
MLS(config-slb-vserver)# shopper 210.one.1.0 0.0.0.255
SLB could be the server stop’s respond to to HSRP, VRRP, and GLBP – but you 먹튀검증 still have to know it to become a CCNP! Knowing redundancy approaches and protocols is vital in today’s networks, so ensure that you’re relaxed with SLB ahead of taking over the Examination.