On Thu, Feb 28, 2013 at 11:13 PM, Caloocan Gangsta <[email protected]> wrote: > Hi Pluggers, > > Would like to get your suggestion and howtos in providing high availability > on my two server that will host Apache, i need to have a redundant > connectivity even one of the server will fail. > > Thanks, > > Bong
hi bong, how many 9's uptime percentage are you trying to achieve? The more 9s you have the more redundant of network devices you need such us redundant routers, load balancers, switches, servers, storage as well as your upstream links... for enterprise designs... not only those above are redundant.... even the locations too and implementing global load balancing... there are two types of highly availability - active-active and active-standby active-active full use of your capacity while active-standby use one half of your capacity.. highly availability is different with highly scalability... even though you have servers doing a highly availability but your upstream link, router or load balancer is only one or not in highly availability setup and one of them fails... your number of 9s will be affected to this... that is why you need to understand your uptime needs.... for server highly availability.. you go for hardware based load balancers (eg. foundry, alteon, F5, cisco, etc) or software based load balancers (eg. LVS).. going for load balancer solution either hardware or software based requires additional hardware investment.. my last design there in Philippine ISP before I left the country is to implement a highly availability and scalability to all regions we have point of presence (POP) without using a load balancer due to budget constraint... services running in POP with highly availability and scalability are DNS and PROXY both in active-active setup with 1 second failover to a good active server.. i wrote a customize C network program to mimic how load balancer do a health check to a service with a combination of one existing network protocol to help the availability of layer 3 health status.... fooler. _________________________________________________ Philippine Linux Users' Group (PLUG) Mailing List http://lists.linux.org.ph/mailman/listinfo/plug Searchable Archives: http://archives.free.net.ph
