Re: GUI-Dev

[Maj Justin Seiferth <se...@www.disa.mil>]

Harrie, et al:

I've integrated the Advent SNMP java-based toolkit into the GUI I've
been working on- I can establish contact with snmpd and retrieve system
information (from the OS obviously, not Apache) so I now is the time to
start worrying about a configuration mib and how to integrate this into
the server end.

How would you fashion the configuration MIB and is the separate server
idea still the best one for doing something which can read/write config
files?  With the dynamic nature of the config directives I'm not sure
what the best structure for a configuration MIB might be.

Justin
seiferth@erols.com

A possible APACHE-MIB for the configuration

[Harrie Hazewinkel <ha...@jrc.it>]

Hi,

Oops... I forgot to attach the MIB itself. :-((
Hereby the MIB.

-- 
HA HA
0- Harrie Hazewinkel --------------------------------------0
 mailto:harrie.hazewinkel@jrc.it       phone:+39+332+789384
 http://porto.jrc.it/~harrie/            fax:+39+332+785500
 postal: JRC of the E.C.  -  CEO unit
         Ispra 21020 (VA) Italy
0----------------------------------------------------------0
  Ik ben Harrie en ik ben 28 jaar en doe SNMP na. MIB, MIB

A possible APACHE-MIB for the configuration

[Harrie Hazewinkel <ha...@jrc.it>]

HI,

A long time ago we psoke about the possibility of using
SNMP and MIbs for the possible configuration of 
the Apache server.

Hereby I sent some preliminary ideas about this MIB.
It is mainly consisting of tables which are indexed by
the 'sysApplRunIndex' of the SYStem APPLication - MIB.
This doesn't mean that this SYSAPPL-MIB has to be
implemented to, but it is used only in case someone
does and then multiple invocations of Apache on the
same system are possible.

I believe especialy the first table is quite useful.
I hope you can understand my ideas so far. I plan to provide
a more complete desription in the future. These are my
first ideas.


HA HA
0- Harrie Hazewinkel --------------------------------------0
 mailto:harrie.hazewinkel@jrc.it       phone:+39+332+789384
 http://porto.jrc.it/~harrie/            fax:+39+332+785500
 postal: JRC of the E.C.  -  CEO unit
         Ispra 21020 (VA) Italy
0----------------------------------------------------------0
  Ik ben Harrie en ik ben 28 jaar en doe SNMP na. MIB, MIB

SNMP MIB Structure

[Calvin Justin Seiferth <se...@www.disa.mil>]

Harrie,

I had thought about dividing the MIB into tables for "core", "modules"
and "contributed" sections. Why?

Accounting for all the directives in one big MIB seems like a tough task
to me but breaking it up into variables associated with the major parts
seems workable- allowing the MIB to stay fairly stable across Apache
versions and various combinations of modules/functionality.

Each SNMP variable would be a string whose value would need to be parsed
to strip out the relevant info. For instance we could pass:

www.disa.mil:specialized.domain.mil:documentdirectory/subdirectory:directive:directive_value

as the value for the "core" variable.

I couldn't find a MIB which used this approach or addressed this issue
in an alternative way; any suggestions or does this seem like a workable
approach?

If the approach does seem workable here are some areas that are
confusing to me:

I don't understand how tables are constructed and queried very well.
Could you help me out in this area?

What object type would you recommend using?  It can't have any arbitrary
upper limit on length since my context idea could extend to very long
strings as it moves down a complex directory structure for instance
although perhaps 512 - 1024 characters would allow for this instance.

What are the particulars of the calling sequence which allows the
managed entity (aka the configuration server), snmpd and the agent to
interact.  I understand the snmpd <-> agent communication but how is the
snmpd<->configuration server communcation handled?  From the code I have
read it seems as if the configuration server "registers" itself with
snmpd and then snmpd in turn then just queries the managed object when a
get request is received or sends in a new value when a set directive is
issued.  Is this correct and are then intracacies here?  I was planning
on implementing this by just snagging what seemed to be the relevant
bits of mod_snmp.

Thanks...
Justin

Re: GUI-Dev

[Harrie Hazewinkel <ha...@jrc.it>]

Maj Justin Seiferth wrote:
> 
> Harrie, et al:
> 
> I've integrated the Advent SNMP java-based toolkit into the GUI I've
> been working on- I can establish contact with snmpd and retrieve system
> information (from the OS obviously, not Apache) so I now is the time to
> start worrying about a configuration mib and how to integrate this into
> the server end.

I work on an upgrade of the SNMP-module for Apache in order to get
it in line with the IETF defined WWW-MIB.

> 
> How would you fashion the configuration MIB and is the separate server
> idea still the best one for doing something which can read/write config
> files?  With the dynamic nature of the config directives I'm not sure
> what the best structure for a configuration MIB might be.


I have tried to think of something for a configuration MIB.
I believe this is quit difficult, since a lot of different
directives have to be grouped. Once this is done.
We have to write the tables in which the values can be set.
We also have to decided if we go for a more general option
or specific. 
We have somehow to choose between:
a) a table in which 1 entry for 1 installed Apache has 
lots of columns (in which each a seperate managed objects 
(configuration directive) is defined.

or 

b)
every configuration directive has a seperate entry.



For the choice of putting the configuration inside apache or 
outside. The choice is do we want to "sighup" Apache after each 
change in configuration. I believe the most easiest way is via
config-files, but this is actually not prefered, because
before responding an SNMP-set it must be sure that
the SNMP-set operation is possible. IMHO, this
is directly required if config files are used and
there can become inconsistencies between the running
configuration and the SNMP-setted configuration.



-- 
HA HA
0- Harrie Hazewinkel --------------------------------------0
 mailto:harrie.hazewinkel@jrc.it       phone:+39+332+789384
 http://porto.jrc.it/~harrie/            fax:+39+332+785500
 postal: JRC of the E.C.  -  CEO unit
         Ispra 21020 (VA) Italy
0----------------------------------------------------------0