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Full Discussion: Interpretation of Ping behaviour
Top Forums UNIX for Advanced & Expert Users Interpretation of Ping behaviour Post 302921802 by jim mcnamara on Monday 20th of October 2014 11:21:34 AM
Old 10-20-2014
/etc/resolv.conf just enumerates the order and names of dns servers to check. You
may need to modify that. We use several dns servers in out network - two infoblox appliances and one windows domain controller.

As Made_in_Germany said, /etc/nsswitch.conf controls where to look in general.

Is your cache name service daemon running? Turn on dns caching.

Code:
/fmd> svcs /system/name-service-cache
STATE          STIME    FMRI
online         Oct_17   svc:/system/name-service-cache:default

Should say 'online'

Next check performance of the caching with
Code:
nscd -g

You want to see:
Code:
CACHE: hosts

         CONFIG:
         enabled: yes
         per user cache: no
         avoid name service: no
         check file: yes
         check file interval: 0
         positive ttl: 3600
         negative ttl: 5
         keep hot count: 20
         hint size: 2048
         max entries: 0 (unlimited)

         STATISTICS:
         positive hits: 39
         negative hits: 2
         positive misses: 2
         negative misses: 3
         total entries: 2
         queries queued: 0
         queries dropped: 0
         cache invalidations: 0
         cache hit rate:       89.1


CACHE: ipnodes

         CONFIG:
         enabled: yes
         per user cache: no
         avoid name service: no
         check file: yes
         check file interval: 0
         positive ttl: 3600
         negative ttl: 5
         keep hot count: 20
         hint size: 2048
         max entries: 0 (unlimited)

         STATISTICS:
         positive hits: 1104
         negative hits: 2
         positive misses: 25
         negative misses: 3
         total entries: 4
         queries queued: 0
         queries dropped: 0
         cache invalidations: 18
         cache hit rate:       97.5

You may need to increase your local dns cache size. Primarily what you need is a sysadmin/network admin who knows this stuff, and is not following a rote playbook for how to maintain a network.

The optimal solution for dns problems like this is most often to set up caching DNS servers, and turn off nscd.

As a side note, it is very slightly possible your cache is becoming stale, possibly a DNS server has problems. If the cache stuff is working you may want to bounce the nscd process. This will clear the caches. So if an immediate rerun of your problem continues, then you have other issues, which IMO tend to be nasty.

N.B.:
This kind of advice is hard to give without actually being there, too many moving parts to do a decent job vicariously like this.
 

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LEARN ABOUT SUNOS

asadmin-jms-ping

asadmin-jms-ping(1AS)						   User Commands					     asadmin-jms-ping(1AS)

NAME

       jms-ping  - checks to see if the JMS provider is up and running

SYNOPSIS

       jms-ping   --user  admin_user  [--password  admin_password]  [--host  localhost]  [--port  4848]  [--passwordfile  filename]  [--secure|-s]
       [--terse=false] [--echo=false] [--interactive=false]

       Checks to see if the JMS provider is up and running. This command is supported in remote mode only.

OPTIONS

       --user		       authorized domain application server administrative username.

       --password	       password to administer the domain application server.

       --host		       machine name where the domain application server is running.

       --port		       port number of the domain application server listening for administration requests.

       --passwordfile	       file containing the domain application server password.

       --secure 	       if true, uses SSL/TLS to communicate with the domain application server.

       --terse		       indicates that any output data must be very concise, typically avoiding human-friendly sentences and favoring well-
			       formatted data for consumption by a script. Default is false.

       --echo		       setting to true will echo the command line statement on the standard output. Default is false.

       --interactive	       if set to true (default), only the required password options are prompted.

       Example 1: Using jms-ping

       asadmin> jms-ping --user admin --password adminadmin --host bluestar --port 4848 server1
       JMS Ping Status=RUNNING

EXIT STATUS

       0		       command executed successfully

       1		       error in executing the command

       asadmin-create-jmsdest(1AS), asadmin-delete-jmsdest(1AS), asadmin-list-jmsdest(1AS)

J2EE 1.4 SDK							    March 2004						     asadmin-jms-ping(1AS)
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