Performance issue ( maybe )

[Bjarne Blichfeldt]

> -----Original Message-----
> From: Tom Schmitt
> Sent: 6. september 2010 14:27
> To: Users of ISC DHCP
> Subject: Re: RE: Performance issue ( maybe )
> 
> 
> > Von: Bjarne Blichfeldt <bjb at jndata.dk>
> > Betreff: RE: Performance issue ( maybe )
> 
> 
> > No, but I have noticed that the all the balancing lines seems to be
> > duplicated :
> > Sep  3 06:53:40 b00011100859 dhcpd: balancing pool 9c8de78 10.229.16.0/24
> > total 248  free 124  backup 124  lts 0  max-own (+/-)25
> > Sep  3 06:53:40 b00011100859 dhcpd: balanced pool 9c8de78 10.229.16.0/24
> > total 248  free 124  backup 124  lts 0  max-misbal 37
> 
> These are no duplicates, this is the normal behaviour:
> 1 line balancing
> 1 line balanced
Ah ok, I see that now.

> 
> 
> 
> > And one (of many different) specific :
> > Sep  3 08:19:53 b00011100859 dhcpd: balanced pool 8a552c0 10.20.65.0/24
> > total 199  free 102  backup 88  lts 7  max-misbal 29
> > Sep  3 08:20:56 b00011100859 dhcpd: balanced pool 8a552c0 10.20.65.0/24
> > total 199  free 102  backup 88  lts 7  max-misbal 29
> > Sep  3 08:21:50 b00011100859 dhcpd: balanced pool 8a552c0 10.20.65.0/24
> > total 199  free 102  backup 88  lts 7  max-misbal 29
> 
> This is a very short timeframe (one minute) between your logline. Afaik there
> are two reasons you get all these balance-lines: If one of the servers is
> doing a restart or on a regulary basis, depending what time-values you have
> configured in your failover paragrahp.
> 
> One minute is okay if you only have a few subnets. But if you have a bigger
> amount of subnets you should consider a higher value. For example, I have set
> this value to 2 hours.
Sorry not sure which timer value you mean here ?

> 
> 
> Only to negate the other possibility:
> Are you sure, one of your server isn't constantly restarting? For example,
> your second dhcp-server has a corrupt RAM and the dhcpd is sefaulting and
> crashing but some kind of monitor-process is immideately restarting it.
> This would result in a picture you saw.
> (And because you only looked in the logfile of the first server you didn't saw
> the restarting messages.... :-)
> Okay, far fetched.
Not so far fetched, see my previous mail. We had a lot of failover timeouts, starting the afternoon before.
Then it just went south from there.

Regards, 
Bjarne