[erlang-questions] Controlled interaction of two erlang distributed networks

Ulf Wiger ulf.wiger@REDACTED
Wed Aug 26 09:43:07 CEST 2009

Jayson Vantuyl wrote:
> One more note.  You may also need to use the option "-connect_all 
> false".  It keeps from having the nodes automatically connect to all of 
> the nodes that a partner is connected to.  I always forget about that one.

I don't think mixing global and connect_all false is a good idea.
The docs for global mention connect_all, but also say that only
locking, not name registration, will work then.

BTW, I found this fairly confusing wording in the global_group
man page:

"For the processes and nodes to run smoothly using the global group 
functiontionality, the following criteria must be met:

- ...
- *All* nodes in the system should belong to exactly one global group."

Presumably, it should be "Every node in the system should belong
to exactly one global group."

As it reads now, it could easily be interpreted as requiring that
there must be exactly one global group, and all nodes must be
members of that group - apart from the fact that this would
clearly be absurd, as it would eliminate any reason for using
global_group in the first place...

Ulf W

> On Aug 25, 2009, at 8:20 PM, Richard Andrews wrote:
>> On Wed, Aug 26, 2009 at 11:28 AM, Jayson Vantuyl<kagato@REDACTED> wrote:
>>> You might ask why I wouldn't just monkey with Distributed Erlang to 
>>> separate
>>> the globals into groups (see the global_group module).  The problem 
>>> is that
>>> Distributed Erlang still just isn't built for this sort of use-case.  In
>>> Distributed Erlang getting the SSL stuff working right is hard, 
>>> firewalls
>>> suck, NAT sucks even more, and the proper DNS setup is more trouble than
>>> maintaining a node-list ever was (and impossible to quickly fix, if 
>>> you use
>>> high enough TTLs).
>> Security, NAT, etc. is a non-issue as any non-LAN traffic travels via
>> IPSec between sites. Do you think this modifies your suggestions?

Ulf Wiger
CTO, Erlang Training & Consulting Ltd

More information about the erlang-questions mailing list