Re: [squid-users] squid mirror

hi

can u send me the demonstrating FT video link ?

Thanks

On 07/21/2010 12:37 PM, Alex Braunegg wrote:
> Hi,
>
> There are a number of ways to tackle this problem, however I have solved
> this by using VMware and VMware Fault Tolerance.
>
> VMware Fault FT is a technology based on vLockStep that provides continuous
> availability in the event of physical ESX server failure by creating a
> shadow virtual machine which is in step with the primary machine. What this
> means for Squid is that you are running a single instance of Squid on your
> ESX(i) cluster in FT protected mode. Should the physical host fail, the
> Squid instance shadow copy kicks in with near instantaneous effect. No
> connections / interruptions to traffic occurs, and the end users are none
> the wiser as all connections are persistent through the outage.
>
> The limitation of VMware FT however is that it constrained to one vCPU - but
> for Squid I don't think that this is a massive issue. Solving the problem of
> lockstep for 2 single CPU virtual machines is much simpler than multi CPU
> virtual machines. The underlying technology for vLockstep uses record /
> replay to record the indeterministic input from one VM and replay it on the
> second VM over a specific configured logging network. While this works great
> for single CPU's in vSMP environments shared memory access by the CPU's is
> not deterministic - hence recording only inputs from one virtual machine and
> replaying them on another machine does not guarantee deterministic replay to
> exactly replicate the original environment. This makes FT for vSMP
> distinctly harder and a much more different problem to solve. It is unknown
> at this point in time as to when vSMP support will be available for VMware
> FT - even with the release of VMware ESX(i) 4.1 there is no change in this
> arena.
>
> If you are using VMware within your environment, have a look at VMware FT. I
> do have video's demonstrating FT in operation when dealing with web content
> highlighting the persistence of connections during failover.
>
> Best Regards,
>
> Alex
>
> -----Original Message-----
> From: viswa [mailto:waytoviswa_at_gmail.com]
> Sent: Wednesday, 21 July 2010 4:48 PM
> To: squid-users_at_squid-cache.org
> Subject: [squid-users] squid mirror
>
> hi all
>
> i am using two squid servers with HA Cluster. Always one squid server is
> responds to clients another one for backup.
> If the squid one is down the another squid server responds to
> clients.And my problem is persistent connection . is this possible to
> continue to client persistent connection after the squid one failure ??
> is possible to mirror squid connections to another squid??
>
> Thanks
>
>
>
>
Received on Wed Jul 21 2010 - 07:23:00 MDT