Re: [HTCondor-users] Multiple Collectors + CCB & Shared Port

[Todd L Miller <tlmiller@xxxxxxxxxxx>]

> # Ability for multiple sub-collectors on a single machine
> COLLECTOR.NumProcesses = 4

	I don't see this in the manual, and as far as I know is 
unnecessary for what you're doing.  There's COLLECTOR_QUERY_WORKERS, which 
is how many times the collector will fork to answer a query, but that's 
not really the same thing.

> > COLLECTOR_HOST                  = $(CONDOR_HOST):20000

	This is a little weird, because it will make the collector at port 
20000 the 'main' collector, and everything will query the collector behind 
the shared port by default, which won't know everything.

	If all you want is some extra CCBs, you don't need to change 
COLLECTOR_HOST at all.  You need to set CCB_ADDRESS in the clients, but 
that's all you need to do.

> Can somebody point me in a direction what I'm doing wrong regarding the 
> combination of CCB + Shared Port together with multiple sub-collectors?

	If you /want/ to have multiple ports open, you need to turn off 
shared port in the sub-collectors.  The standard way to do this is to add 
_CONDOR_USE_SHARED_PORT=FALSE to the environment line you already have 
defined.


	If you /can't/ have multiple ports open, then using -sock in the 
_ARGS configuration should set the shared port socket name for those 
collectors.  If you're just using the sub-collectors for CCB, you should 
be able to set an execute node CCB_ADDRESS to a string like 
1.2.3.4:9618?sock=collector2 without any further worries.  (This may have 
to be '<1.2.3.4:9618?sock=collector2>' -- with the <brackets> -- or could 
be different, depending on other details of your networking configuration; 
the easiest way to find it is probably to look up another daemon (not the 
collector) running on the same machine and replace the 'sock=value' 
appropriately.)  If you want the sub-collectors to help deal with 
expensive security sessions, you'll need to set the execute node's 
COLLECTOR_HOST instead, which may cause further problems (IIRC, the 
default security configuration uses COLLECTOR_HOST, but strings of the 
form above don't work in security).

	If you go for multiple collectors behind a single shared port, you 
may have some trouble configuring your execute nodes to actually do the 
load balancing.  RANDOM_CHOICE() may approximate what you want 
sufficiently well to get started.


	I'm not sure there's a way to support both arbitrary socket 
numbers and shared port (in the same daemon), although you'd have to 
explain to me why you'd want to do that.

- ToddM