|
At 07:12 PM 4/24/00 -0400, Joseph Mack wrote:
>On Mon, 24 Apr 2000, Wayne wrote:
>
> > We have tested LVS with DNS, which is UDP based, too.
>
>DNS occassionally issues tcp requests too, which might muddy the waters. I
>tested LVS on DNS about 6 months ago at moderate load (about 5/sec I
>believe) and it behaved well. I don't remember looking for exact balance
>and I doubt if I would have regarded a 50% imbalance a problem. I was just
>seeing that it worked and didn't lock up etc.
I tested at about 100 requests per seconds, and it works fine.
As you mentioned, it doing little bit TCP when DNS do the
zone transfer.
> > What we are doing with this test is not for heavy load
> > issue, rather to see if LVS can provide a fail-over
> > mechanism for the services. By load balancing the
> > servers, we can make two servers backup one, if the
> > one failed, the service will not stop.
>
>I image you have your reasons, but if yu have two ntp servers at the same
>stratum level and the rest of the machines are slaves, the whole setup
>will keep functioning if you pull the plug on one of the two servers. Will
>LVS give you anything more than that?
>
Trying to test a absolute high availability solution. When one server
down, the load will increase to other two. When two servers down,
the load will be triple for the only surviving server. By this
configuration, adding new servers will not change anything for
the clients, so for any failure after the LVS box, it has not
impact for other computers.
> > If round-robin does this one request per server, it is
> > pretty hard to explain what we saw at the server log,
> > which indicating one server getting twice the requests
> > than other two in some seconds, and getting a lot less
> > at other seconds. Could you explain why we seeing
> > that?
>
>sorry no idea. Will set it up myself and have a look. Probably won't be
>able to do it for a few days, but since someone else is interested too...
>
>are both your realservers at the same stratum level? (I can't imagine any
>other way of doing it, but thought I'd check)
>
>Are you doing VS-DR or VS-NAT?
Yes, all three servers at the same stratum and doing NAT.
Thanks so much, Joe.
>Joe
>
>--
>Joseph Mack mack@xxxxxxxxxxx
|
