16 Zenoss Core Daemons – Complete List of all ZenOSS Process

by Sandeep Krishnan on February 3, 2014

Zenoss Core has lot of daemons that can be used for various purpose.

While you might not use all of the daemons in your Zenoss environment, it is still essential for you to understand all available zenoss daemons, which you can use to solve a specific enterprise monitoring requirement.

In Zenoss v4 all daemons interact with Mysql and zenhub. By default all the zenoss daemons run in info mode.

1. zeneventserver

In Zenoss 3.1.1 the event processing was managed by zenhub daemon because of that there was bottleneck in event processing which has caused some performance related issues, so to avoid that in Zenoss 4.x they have introduced new daemon zeneventserver.

zeneventserver daemon which is written in java, interact with Rabbitmq and fetch the events from zenevents queue[zenoss.queues.zep.zenevents]and insert into the events tables that are in zenoss_zep database where the events are getting stored.

Another responsibility of this daemon is to fetch the event related information like [resource, summary, last seen, first seen, severity etc.], in Java Script Object Notation [JSON] format so that it get displayed in zenoss UI also moves the event to zenoss zenoss.queues.zep.signal queue. Zenpack installation is taken care by this daemon. [Event Class creation while installing zenpack]

cat /opt/zenoss/etc/zeneventserver.conf [config file of zeneventserver]
zep.jdbc.dbname=zenoss_zep
zep.jdbc.hostname=localhost
zep.jdbc.port=13306
zep.jdbc.password=xxxxxx
zep.jdbc.username=xxxxxx

Note: if we stop zeneventserver daemon and check rabbitmq queues by the command [rabbitmqctl -p /zenoss list_queues], we could see value of queue zenoss.queues.zep.zenevents gets increasing.

# zeneventserver stop [Need to run as zenoss user]

# rabbitmqctl -p /zenoss list_queues
Listing queues ...
celery  0
zenoss.queues.zep.migrated.summary      0
zenoss.queues.zep.migrated.archive      0
zenoss.queues.zep.rawevents     0
zenoss.queues.zep.heartbeats    0
zenoss.queues.zep.zenevents     12
zenoss.queues.zep.modelchange   0
zenoss.queues.zep.signal        0
...done.

Once we start zeneventserver we can see the queue count get back to ‘0’ [Zero]

If you are new to zenoss, install zenoss core and start exploring these daemons.

2. zenhub

zenhub daemon is written in python. Event processing gets triggered when zenhub daemon gets data from other daemons. In paid version zenoss has included invalidation worker process for better performance. In distributed zenoss architecture we normally deploy a Linux VM and which will be running zenhub daemon only. It’s the central point of failure of events getting displayed in zenoss.

3. zenping

zenping daemon does normal ping on interface and the polling interval is one-minute. If the interface is down zenoss generate an alert with critical severity. If the interface comes up zenoss automatically clears the error event with a clear message. zenping has ability to get data point for ping monitoring and can be used to generate availability graphs for the monitored device [Feature in Zenoss4]. The following runs this daemon in debug mode against a device, and used mainly for debugging.

zenping –d x.x.x.x –v10

4. zeneventd

zeneventd daemon has a major role in applying transforms [Python code written to manipulate events]. Daemon fetches incoming events from zenoss.queues.zep.rawevents queue and applies transform add necessary device context such as Device group/Device State [Production/Development] and some event related information such as [last seen, first seen] time of event. If the daemon stops running, we could see size of rawevents queue getting increased. We can debug execution of transform code by putting log.info(‘For Debug’) statement inside the code which will be printed in ‘/opt/zenoss/log/zeneventd.log’

# zeneventd stop 

# rabbitmqctl -p /zenoss list_queues
Listing queues ...
celery  0
zenoss.queues.zep.migrated.summary      0
zenoss.queues.zep.migrated.archive      0
zenoss.queues.zep.rawevents     10
zenoss.queues.zep.heartbeats    0
zenoss.queues.zep.zenevents     0
zenoss.queues.zep.modelchange   0
zenoss.queues.zep.signal        0
...done.

# zeneventd run –d x.x.x.x –v10 

5. zensyslog

zensyslog daemon process syslog messages [/var/log/messages] that are received from monitored device on to zenoss on port UDP/514.

6. zenprocess

zenprocess daemon, process monitoring capability is integrated to zenoss by using HOST-RESOURCES MIB which get loaded into zenoss as part of default installation. zenprocess uses snmp table and get process information like PID, path to the binary that is being executed and number of running instances.
Etc. zenprocess daemon deafult polling interval is 3 min [180 seconds]. Not possible to customize the polling interval per device level. The following runs this daemon in debug mode against a single device.

zenprocess run –d x.x.x.x –v10

7. zenstatus

zenstatus daemon monitors TCP/UDP services that are available on the device such as [http/https/net-bios/].

8. zentrap

zentrap daemon process the incoming traps that are send from hardware on port UDP/162. The daemon decodes the incoming trap to a format that is understandable by zenoss [Python dictionary format] and handover to zeneventd for further processing and to generate events.

9. zenactiond

zenactiond daemon the daemon interact with signal queue in Rabbitmq and trigger notification via Email/Paging/etc. Signal queue get piled up if this daemon stops running.

# rabbitmqctl -p /zenoss list_queues
Listing queues ...
celery  0
zenoss.queues.zep.migrated.summary      0
zenoss.queues.zep.migrated.archive      0
zenoss.queues.zep.rawevents     0
zenoss.queues.zep.heartbeats    0
zenoss.queues.zep.zenevents     0
zenoss.queues.zep.modelchange   0
zenoss.queues.zep.signal        5
...done.

# zenactiond start

10. zenperfsnmp

zenperfsnmp daemon collects performance metrics such as CPU, Memory, File system Usage via snmpwalk and store the information in RRD [Round Robin Database] files, the data collection interval is 300 sec by default. The poll time interval is not customizable per device level, if we change it, it get reflected globally. The following runs this daemon in debug mode against a single device.

zenperfsnmp run –d x.x.x.x –v10 

11. zencommand

zencommand daemon is capable of running custom scripts against the device over ssh, to achieve this ssh username/password need to be configured in zenoss for each monitored device, which is hard if we are monitoring a huge DC. So performance monitoring is done by configuring net-snmp on client device.

zencommand run –d x.x.x.x –v10

12. zenmodeler

zenmodeler daemon gets initial device information such as interfaces/filesystem/ipservices etc. The daemon polling interval is 12hrs by default. It mainly detects configuration changes that happen on device eg: Additional interface gets added, new partition etc.

zenmodeller run –d x.x.x.x –v10

13. zenrrdcached

zenrrdcached daemon is a performance enhancer, helps to cache RRD metrics in the memory, which is used to generate graphs in zenoss. If the daemon fails to fetch the metrics from the memory it will get the metrics from rrd files that is stored in the file system.

14. zopectl

zopectl daemon is call zopeclient, used while developing zenpack. To reflect the code change that we make during zenpack development this daemon need to be restarted.

zopectl restart

15. zenjobs

zenjobs daemon run background tasks like discovering network or adding device these tasks gets added to queue and zenjobs process them. Once a device gets added successfully [Discovered] modeling happens with the help of zenmodeler daemon and returns a job ID. If we want to add devices in a bulk we use zenbatchload command utility.

16. zenrdis

zenrdis daemon is used to collect distributed ping-tree data from collector to build a complete map.

In zenoss each daemon has a config file that is located in /opt/zenoss/etc/ directory. By default all daemons are in info mode. There are two ways to enable debug mode for daemons.

  1. Edit config file for daemon change logseverity 10
  2. daemon name debug Eg: zeneventd debug [toggle daemon between Info and Debug mode]

By listing Rabbitmq queue one can easily determine whether zenoss is working without any problem or not. If we find any events that get struck in any of the queue, restart the corresponding daemon that is responsible for fetching events.


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{ 1 comment… read it below or add one }

1 Bob February 4, 2014 at 7:46 am

Thanks for the info.
Might be helpful to give a 1 sentence/paragraph description about zenoss since most people may not be familiar with the concept.

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