High Availability

[Marc Volovic]

A number of issues:

First - what. You need to replicate (a) links, (b) storage, (c)  
service machines.

Links are internal and external. Multipath internet connexions.  
Multipath LAN connexions. Multipath storage links. Redund network  
infrastructure (switches, routers, firewalls, IDS/IPS).

Replicate storage. If you use SAN with dedicated links, multipath  
links and storage. Redund storage hardware and add storage  
replication. Add auto-promotion, takeover, and (if possible) partition  
prevention mechanisms. Use STONITH.

Service machines are the easiest to replicte. Simple heartbeat will  
provide a significant level of failover and/or failback. Here,  
likewise, use STONITH or other partition prevention mechanisms.

Under-utilize. 70% duty cycle is good.

Expect costing hikes.

M

---MAV
Marc. Volovic
+972-54-467-6764
marcvolovic at me.com
Sent from my iPhone

On Apr 15, 2010, at 7:35, "Boaz Yahav(berber)" <berber at weber- 
sites.com> wrote:

> I guess this is more a theological question.
>
>
>
> Would you build a web site  infrastructure that needs to be highly  
> available using a single machine where the front end servers are  
> virtual servers?
>
> Is this even considered highly available or might it be what's some  
> may  call "partially highly available J"?
>
>
>
> berber
>
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