If you have servers reporting monitoring with Zabbix running still on Zabbix-Agent 1 version 5.0.X but already migrated the Zabbix-server to Zabbix 6, it is a good idea to update the Agent to Zabbix Agent 6 As sson as possible, as you know lacking behind in version makes updating harder and more complicated task.
Mine and I guess most system administrators experience points that Keeping at the same level of versioning on many applications historically has shown to reduce unexpected errors and bugs but nowadays, the rule of keeping local and remote application ( programs ) at the same version level is regularly broken.
Theoretically Zabbix-Agent (Client) and Zabbix (Server) has a compitability for a certain range of versions (Zabbix agents 2 from version 4.4 onwards are compatible with Zabbix 7.0; Zabbix agent 2 must not be newer than 7.0 – for more on zabbix agent – > server version compitability check here ) and having a slight version difference should not be really a problem but often you might have a third party proxies in between such as haproxy or zabbix-proxy or other network oddities and thus my personal opinion is that for interoperability it is better to keep the Zabbix Clients and Zabbix Servers across the DMZ-ed networks running at same version level.
Some would say I have an old fashion thinking as software and technology is moving forward, but as I see how programming code writing and even software is constantly degradating just a reflection of degradation of human element, I prefer to keep my old know how and always stick to same versioning whenever possible.
Some would wonder then why would I upgrade to Zabbix-agent2 ? , if have to keep the same versioning, the reason is zabbix-agent2 is written in GO Language and is much faster and supposably better piece of software than Zabbix Agent1 that is written in Python.
Moreover having Zabbix agent 2 instead of 1 gives also benefits as you can do a bit more with zabbix and on the other hand the machines are more ready for monitoring in terms of future. To know more about the Benefits of Zabbix Agent2 compared to Zabbix Agent 1 read the Agent vs Agent2 comparison on zabbix website.
With this little introduction, lets proceed with the exact steps to take to upgrade zabbix-agent1 to zabbix-agent2.
1. Check the current installed Zabbix-Agent version
[user@monitored-server ~]$ rpm -qa |grep -i zabb
zabbix-get-5.0.42-1.el8.x86_64
zabbix-sender-5.0.42-1.el8.x86_64
zabbix-agent-5.0.42-1.el8.x86_64
[user@server ~]$
2. Create backup copy of current system working zabbix_agentd.conf
Before messing up with the working zabbix-agent as usual create the necessery backup to prevent later suprises
[user@monitored-server ~]$ cp -vrpf /etc/zabbix/zabbix_agentd.conf /etc/zabbix/zabbix_agentd.conf.bak-$(date '+%Y-%m-%d_%H-%M-%S')
…
3. Check current configured Zabbix repos
[user@monitored-server ~]$ vim /etc/yum.repos.d/zabbix.repo
[zabbix-4.0]
name = zabbix-4.0 – 8
baseurl = http://zabbix-repo-server.com/external/zabbix-4.0/8/$basearch
enabled = 0
gpgkey = http://zabbix-repo-server.com/external/zabbix-4.0/zabbix-official-repo.key
gpgcheck = 1
[zabbix-4.4]
name = zabbix-4.4 – 8
baseurl = http://zabbix-repo-server.com/external/zabbix-4.4/8/$basearch
enabled = 0
gpgkey = http://zabbix-repo-server.com/external/zabbix-4.4/zabbix-official-repo.key
gpgcheck = 1
[zabbix-5.0]
name = zabbix-5.0 – 8
baseurl = http://zabbix-repo-server.com/external/zabbix-5.0/8/$basearch
enabled = 1
gpgkey = http://zabbix-repo-server.com/external/zabbix-5.0/zabbix-official-repo.key
gpgcheck = 1
[zabbix-5.4]
name = zabbix-5.4 – 8
baseurl = http://zabbix-repo-server.com/external/zabbix-5.4/8/$basearch
enabled = 0
gpgkey = http://zabbix-repo-server.com/external/zabbix-5.4/zabbix-official-repo.key
gpgcheck = 1
[zabbix-6.0]
name = zabbix-6.0 – 8
baseurl = http://zabbix-repo-server.com/external/zabbix-6.0/8/$basearch
enabled = 0
gpgkey = http://zabbix-repo-server.com/external/zabbix-6.0/zabbix-official-repo.key
gpgcheck = 1
4. Modify repositories and include the Zabbix Agent6 yum repos
[user@monitored-server ~]$ cp -rpf zabbix.repo zabbix.repo.5.0.rpmsave
As we want to keep only the 6.0 version, leave only the zabbix-6.0 section and enable the repo:
[user@monitored-server ~]$ vim /etc/yum.repos.d/zabbix.repo
[zabbix-6.0]
name = zabbix-6.0 – 8
baseurl = http://zabbix-repo-server.com/external/zabbix-6.0/8/$basearch
enabled = 1
gpgkey = http://zabbix-repo-server.com/external/zabbix-6.0/zabbix-official-repo.key
gpgcheck = 1
5. Update zabbix-agent to zabbix-agent2 and update zabbix-get zabbix-sender versions
To not disrupt reported monitoring for zabbix-agent, don't delete zabbix-agent1 but instead in pararallel install and configure
zabbix-agent2 and then once configuration is migrated from Agent 1 to 2, stop the old zabbix-agent and bring up the new one.
[user@monitored-server ~]$ yum check-update
[user@monitored-server ~]$ yum install zabbix-agent2 zabbix-get zabbix-sender -y
Note that if you want to have a precise version number of zabbix-agent that is lets say 6.0.31 to correspond to zabbix-server 6.0.31 (even though in the repositories newer RPM versions are available), run:
[user@monitored-server ~]$ yum upgrade zabbix-agent2-6.0.31-release1.el8
- Check new zabbix_agent2 installed version
# zabbix_agent2 -V
zabbix_agent2 (Zabbix) 6.0.31
Revision b6d93755a1b 17 June 2024, compilation time: {undefined} {undefined}, built with: go1.21.3
Plugin communication protocol version is 6.0.13
Copyright (C) 2024 Zabbix SIA
License GPLv2+: GNU GPL version 2 or later <https://www.gnu.org/licenses/>.
This is free software: you are free to change and redistribute it according to
the license. There is NO WARRANTY, to the extent permitted by law.
This product includes software developed by the OpenSSL Project
for use in the OpenSSL Toolkit (http://www.openssl.org/).
Compiled with OpenSSL 1.1.1k FIPS 25 Mar 2021
Running with OpenSSL 1.1.1k FIPS 25 Mar 2021
We use the library Eclipse Paho (eclipse/paho.mqtt.golang), which is
distributed under the terms of the Eclipse Distribution License 1.0 (The 3-Clause BSD License)
available at https://www.eclipse.org/org/documents/edl-v10.php
We use the library go-modbus (goburrow/modbus), which is
distributed under the terms of the 3-Clause BSD License
available at https://github.com/goburrow/modbus/blob/master/LICENSE
6. Migrate old /etc/zabbix/zabbix_agentd.conf to /etc/zabbix/zabbix-agent2.conf
For readability to show the main configured variables for zabbix-agent without the tons of comments, to later include in agent2
[root@monitored-server ~]# cat /etc/zabbix/zabbix_agentd.conf | grep -v '\#' | sed '/^$/d'
PidFile=/var/run/zabbix/zabbix_agentd.pid
LogFile=/var/log/zabbix/zabbix_agentd.log
LogFileSize=0
Server=10.50.37.8,127.0.0.1
ServerActive=10.50.37.8,127.0.0.1
Hostname=fqdn-of-monitored-host.domain.com
Timeout=20
Include=/etc/zabbix/zabbix_agentd.d/*.conf
The default zabbix-agent2 installed config would like similar to:
[root@monitored-server ~]# cat /etc/zabbix/zabbix_agent2.conf | grep -v '\#' | sed '/^$/d'
PidFile=/run/zabbix/zabbix_agent2.pid
LogFile=/var/log/zabbix/zabbix_agent2.log
LogFileSize=0
Server=127.0.0.1
# Specify the location of the Zabbix server host.
ServerActive=127.0.0.1
Hostname=Zabbix server
Include=/etc/zabbix/zabbix_agent2.d/*.conf
PluginSocket=/run/zabbix/agent.plugin.sock
ControlSocket=/run/zabbix/agent.sock
Include=./zabbix_agent2.d/plugins.d/*.conf
The new migrate one, should be like:
[root@monitored-server ~]# vim /etc/zabbix/zabbix_agent2.conf
PidFile=/run/zabbix/zabbix_agent2.pid
LogFile=/var/log/zabbix/zabbix_agent2.log
LogFileSize=10
Server=10.34.89.7,127.0.0.1
ServerActive=10.34.89.7,127.0.0.1
Hostname=lqgblu02f.ffm.de.int.atosorigin.com
Timeout=20
Include=/etc/zabbix/zabbix_agent2.d/*.conf
PluginSocket=/run/zabbix/agent.plugin.sock
ControlSocket=/run/zabbix/agent.sock
Include=/etc/zabbix/zabbix_agent2.d/plugins.d/*.conf
7. Add few Optimization variables for better zabbix-server -> zabbix-proxy -> zabbix-server interactions
If you have sometimes a network delays between zabbix server -> zabbix client and vice versa (depending on whether Zabbix agent is configured as Active or Passive mode), it is often useful
to add those 2 variables:
# How often list of active checks is refreshed, in seconds
RefreshActiveChecks=60
# Refresh the active checks on start.ForceActiveChecksOnStart=1
ForceActiveChecksOnStart=1
Also it might be a good practice to add zabbix_agent2.log monitoring with the agent itself, if the log exceeds certain amount, instead of calling it via logrotate.
# Perform log file rotation at the 1 MB point for the specified filepath
LogFileSize=1
[root@monitored-server ~]# vim /etc/zabbix/zabbix_agent2.conf
PidFile=/run/zabbix/zabbix_agent2.pid
LogFile=/var/log/zabbix/zabbix_agent2.log
LogFileSize=10
Server=10.34.89.7,127.0.0.1
ServerActive=10.34.89.7,127.0.0.1
Hostname=lqgblu02f.ffm.de.int.atosorigin.com
RefreshActiveChecks=60
ForceActiveChecksOnStart=1
Timeout=20
Include=/etc/zabbix/zabbix_agent2.d/*.conf
PluginSocket=/run/zabbix/agent.plugin.sock
ControlSocket=/run/zabbix/agent.sock
Include=/etc/zabbix/zabbix_agent2.d/plugins.d/*.conf
8. Stop the old zabbix agent process and run the new one
# systemctl status –full zabbix-agent2
# systemctl stop zabbix-agent
Assuming that the configuratoin of zabbix-agent is correct, execute zabbix-agent2 via system control.and check its status
# systemctl start zabbix-agent2
# systemctl status –full zabbix-agent2
If no errors in the configuration, the zabbix_agent2 process should be up and running and the status of above systemctl cmd should report fine.
If you need concretics regarding exact Zabbix checks or whther current conigured Userparameter scripts errors, or any other warnings or errors
of zabbix_agent2 interacting to the server, check further the logs
[root@monitored-server ~]# tail -n 10 /var/log/zabbix/zabbix_agent2.log
2024/08/06 17:26:52.998749 using plugin 'WebPage' (built-in) providing following interfaces: exporter, configurator
2024/08/06 17:26:52.998760 using plugin 'ZabbixAsync' (built-in) providing following interfaces: exporter
2024/08/06 17:26:52.998794 using plugin 'ZabbixStats' (built-in) providing following interfaces: exporter, configurator
2024/08/06 17:26:52.998804 lowering the plugin ZabbixSync capacity to 1 as the configured capacity 100 exceeds limits
2024/08/06 17:26:52.998820 using plugin 'ZabbixSync' (built-in) providing following interfaces: exporter
2024/08/06 17:26:52.998993 Plugin communication protocol version is 6.0.13
2024/08/06 17:26:52.999018 Zabbix Agent2 hostname: [lqgblu02f.ffm.de.int.atosorigin.com]
2024/08/06 17:26:54.000667 [102] cannot connect to [127.0.0.1:10051]: dial tcp :0->127.0.0.1:10051: connect: connection refused
2024/08/06 17:26:54.000836 [102] active check configuration update from host [lqgblu02f.ffm.de.int.atosorigin.com] started to fail
2024/08/06 17:26:59.344837 Zabbix Agent 2 stopped. (6.0.31)
