Re: Speaking about pure fail over - what about pen itself ?

Dominic Marks wrote:
> Ulric Eriksson wrote:
>>
>> On Mon, 27 Mar 2006 fernando_at_fernandoibanez.com wrote:
>>
>>>> I'm only looking at two boxes, except that they will also balance
>>>> other
>>>> services located elsewhere. Should the separate interfaces that pen
>>>> listens to (not the shared one), be real or can they be virtual ?
>>>> Also, if going with independent LB boxes (such as the original
>>>> example),
>>>> do they need to be powerful boxes ? TIA...
>>>
>>> A simple and cheap way to do failover for pen would be using
>>> failover at the DNS level - with a service like
>>> Zone Edit (http://zoneedit.com/)
>>>
>>> ZoneEdit can test if the server is up and if it is not, it can point
>>> your domain to a different IP possibly on a different network.
>>
>> I'm positive that can't work. The old address will be cached on
>> several levels throughout the Internet and there is no way to clear
>> all those caches from a central point. If they charge money for the
>> service, it's a hoax. Otherwise it's just silly.
>>
>> Multicast in Linux isn't very reliable (or I'm simply incompetent),
>> så the vrrp solution isn't as good as it seems. The easiest solution
>> is to point the domain to two addresses, one for each pen instance.
>>
>> Actually, the easiest solution is to install pen on a single server
>> and forget about it, at least as long as the hardware is reliable.
>>
>> Ulric
>
> You could also use CARP, free and cross platform. Available on
> OpenBSD, FreeBSD, NetBSD, Linux (http://www.ucarp.org/project/ucarp).
> Probably will also make it into MacOS X at some point.
>
> Cheers,
> Dom

Is it pretty much the same as VRRP ? Are there any implementation
notes/faq/etc online anywhere ? Would it work as the cheapskate example ?

TIA...

-- 
°(((=((===°°°(((===========================================