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Conference netcad::hub_mgnt

Title:DEChub/HUBwatch/PROBEwatch CONFERENCE
Notice:Firmware -2, Doc -3, Power -4, HW kits -5, firm load -6&7
Moderator:NETCAD::COLELLADT
Created:Wed Nov 13 1991
Last Modified:Fri Jun 06 1997
Last Successful Update:Fri Jun 06 1997
Number of topics:4455
Total number of notes:16761

3462.0. "dechub manager losing SNMP requests" by TOOPCS::SELLES () Tue Apr 16 1996 16:49

a customer is trying to setup its snmp application to monitor 
the state of the 32 ports of a decrepeater900tm 

when he issues at the same time 32 snmp "get-pdu" requests for the state of 
each port thru the dechub manager in-band interface relaying to the repeater
agent ,  only half of them are satisfied with "reponse-PDU" : he uses 
the dechub in-band ip address and the "sub-community" for the repeater agent ;
so half are lost in between the dechub manager and the repeater agent  

if he does the same directly to the repeater900 agent using the ip address of
the repeater , all the requests are satisfied and none is lost 

this "losing" of snmp request , is , from the customer , due to the 
constraint of the "internal" management star , which is based on async-like 
38,6Kbps "channels" and to lack of buffering ;

he wonders if this a known restriction and if something is going to be done 
so to avoid losing snmp get-requests 


thanks for your answers 



PS : by the way , i advised him to use "get-next" request a-la-Hubwatch 
but he sticked to it that it should work its way 
T.RTitleUserPersonal
Name
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3462.1Yes, all products can lose management messages.NETCAD::GALLAGHERTue Apr 16 1996 17:3133
>this "losing" of snmp request , is , from the customer , due to the 
>constraint of the "internal" management star , which is based on async-like 
>38,6Kbps "channels" and to lack of buffering ;
>

Your customer is correct.

>he wonders if this a known restriction and if something is going to be done 
>so to avoid losing snmp get-requests 

Yes, it's a known restriction.  And nope, nothing is going to be done about it.

Your customer can also find the limit of the in-band channel to the repeater.
The repeater can't handle an infinite number of requests thru it's in-band
channel either.  No device I'm aware of can handle wire-speed management
requests.

>PS : by the way , i advised him to use "get-next" request a-la-Hubwatch 

Good!  It would be preferable to use a single getNext request to get this
information.

>but he sticked to it that it should work its way 

Maybe you should remind your customer that SNMP is carried over UDP - a
connectionless datagram delivery service in which messages are expected
to get lost occasionally.

By the way, we don't hear must about customers writing custom applications
for our hub products.  Most are pretty happy with HUBwatch or SomthingVISN.
Can you tell us a little more about what the customer is doing, and why?

							-Shawn
3462.2snmp "supervision"TOOPCS::SELLESWed Apr 17 1996 15:4911
Shawn , 

the customer is writing its own "network and system" supervision software
tailored to its own configuration ( mix of digital, timeplex , hp ... )
and in French, around SNMP packages  ; 

they also use Hubwatch and so on for equipement configuration and troubleshooting

thanks for your reply
PJ