Conference azur::mcc

6112.0. "mcc problems with DNS failover to readonly replica server ??" by VNABRW::HAINZL_R () Tue Sep 06 1994 07:13

Configuration :

	2 VAX 4000-90 (FSMCS1, FSMCS2)
	DECnet/OSI 5.6 (DNVVMSMUPB056,DNVOSIMUPB056,DNVOSIB_ECO08056)
	UCX20D
	MCCBMS013
	MCCELMAM013
		patched versions of mcc_concentrator_am.exe
				    mcc_tcpip.exe
				    mcc_ip_poller.exe
				    mcc_iconic_map_pm.exe
				    mcc_notification_fm.exe
	128 MB Mem each
	FDDI and Ethernet Adapter active

	
redundant MCC setup on both machines (same entities, same map's, same rules,
same notifications ...)

using DNS for DECnet/OSI and MCC
	FSMCS1 holds all master replicas
	FSMCS2 holds readonly replicas of all directories
	
	access control setup within DNS
		full access on all dirs, obj, links and clearingh for
		accounts :
			MCC, SYSTEM, DNS$SERVER (both FSMCS1 and FSMCS2)
		r,t for all others :  .*...


problem :

	both machines up, MCC up   --> ok

failover tests :

	1) stopping FSMCS1 (DNS master replicas)  --> FSMCS2 ok

	2) both machines running and stoppin FSMCS2  --> all ok

	3) both machines running, stopping FSMCS1 and
	   rebooting FSMCS2 :

		--> DNS access (readonly ok) 
		--> DECnet/OSI access (node name translation) ok
		
Problem :	when starting MCC after rebooting DNS-replica-server 
		(with unavailable Master - Server):

		!!! it takes an awful long time  (15 minutes to start compared
		to 1.5 minutes in regular operation)
		
		experiencing the following errors within MCC:

		a) DNS-E-RESOURCEERROR Insufficient Resources to Process Request

		b) DNS-E-TIMEOUTNOTDONE Clerk Timeout occured before any 
			modifications completed

		the above errors were fixed by increasing DNS-Server quotas in
		DNS$SERVER_STARTUP.COM


		whats still remaining is :
		- 15 minutes to see the map
		- polling rules started in batch job don't work --> 
		  no notifications seen 
		- MCC-processes seem to hang (clicking on MCC iconic map
		  windows show reactions only after minutes).

		low load on the machine  CPU %  <<  5%
					 DIO    << 40 DIO's/sec
					 BIO    << 20 BIO's/sec
					 lots of memory


btw.: MCC_DNS_CONF = "LOW" is the standard setting
		but deassigning the logical doesn't help.

		- after starting MCC 

		DNS$CHFAIL.LOG  shows:

		NOCOMMUNICATION / NOAPPLICATION errors regarding
		FSMCS_CH (this the masters clearinghouse ...ok)

		but also regarding
		FSMCS2_CH (the readonly servers clearinghouse)

any help highly appreciated

Richard 

btw.: lengthy DNS server and clerk traces and log files available if needed