[CentOS] Implementing LVS changes made in Piranha GUI

Thu Sep 25 20:36:00 UTC 2008
David Dyer-Bennet <dd-b at dd-b.net>

On Thu, September 25, 2008 14:43, Barry Brimer wrote:
> Quoting David Dyer-Bennet <dd-b at dd-b.net>:
>> On Thu, September 25, 2008 14:13, Barry Brimer wrote:
>> > Is the service itself active?
>> >
>> > Do you have a line above these that says something like:
>> >
>> > virtual example.com {
>> >      active = 1
>> Yes; and it shows as active in Piranha, too, and nannys got started for
>> the three real servers.  It just didn't tell ipvs to actually route to
>> them.
> What happens when you run the service check by hand?

Don't know what "service check" means (guessing you mean what nanny does
to decide a service is working?).  But raising the issue of whether
something below the level of what I thought I had changed was changed has
been somewhat productive.

While I can ping the realservers, turns out I can't access the services on
them.  Don't know why yet, but that's something I can investigate.  (Still
don't see why it changed when it did; but if I can't access the services
from the lvs, then it can't route to them either, and the nanny checks
will fail, etc., so that must be fixed before anything can work.)  I will
chase this down, and either fix it or have different questions :-).  Thank

> Do you have your IP addresses for different services on different devices

Yes, they're on separate devices, and they're set up the same was as when
it worked yesterday, so I don't think it's anything that basic that's

I think I've been mis-understanding the startup order.  Is this what
really happens:

1. pulse started

2. lvsd started by pulse

3. nanny for each (active) realserver started by lvsd

4. When a nanny gets a successful test, either it or lvsd *then* enables
that realserver for receiving traffic

That would explain why I have nannys running, but no realservers listed by
ipvsadm.  I expected things to start out on, and only get turned off if
the nannys failed; but in fact doing what I listed above makes more sense,
it's better if you *have* a nanny to make sure the nanny reports ok
David Dyer-Bennet, dd-b at dd-b.net; http://dd-b.net/
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