Hoping someone can help troubleshoot this issue.
I have started getting getting gaps in bandwidth graphs (actually, periods of 0Mb/s) but only on two devices.
E.G.

Manually running mrtg doesnt show any issues, and as you can see, its an intermittent Issue.
Also it occurs on two devices on the network, but not on any others.
I'm now not entirely sure as to where to continue the troublshooting.
Thanks
Matthew
Nagios XI - System Info
System
Nagios XI version: 5.6.13
Release info: auqlddcnms1di.network.jbssa.com.au 3.10.0-1062.4.3.el7.x86_64 x86_64
CentOS Linux release 7.7.1908 (Core)
Gnome is not installed
Apache Information
PHP Version: 5.4.16
Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:75.0) Gecko/20100101 Firefox/75.0
Server Name: nagiosxi.jbssa.com.au
Server Address: 10.207.231.149
Server Port: 443
Date/Time
PHP Timezone: Australia/Brisbane
PHP Time: Thu, 16 Apr 2020 09:17:02 +1000
System Time: Thu, 16 Apr 2020 09:17:02 +1000
Nagios XI Data
License ends in: RPPVMQ
UUID: e2fb8256-cc49-4590-be58-87fe05cbaad4
Install Type: source
└─53395 /usr/local/nagios/bin/nagios -d /usr/local/nagios/etc/nagios.cfg
└─1839 /usr/local/nagios/bin/npcd -d -f /usr/local/nagios/etc/pnp/npcd.cfg
└─53345 /usr/local/nagios/bin/ndo2db -c /usr/local/nagios/etc/ndo2db.cfg -f
CPU Load 15: 1.58
Total Hosts: 662
Total Services: 1960
Function get_base_uri() returns: https://nagiosxi.jbssa.com.au/nagiosxi/
Function get_base_url() returns: https://nagiosxi.jbssa.com.au/nagiosxi/
Function get_backend_url(internal_call=false) returns: https://nagiosxi.jbssa.com.au/nagiosxi/ ... rofile.php
Function get_backend_url(internal_call=true) returns: http://localhost/nagiosxi/backend/
Ping Test localhost
Running:
/bin/ping -c 3 localhost 2>&1
PING localhost (127.0.0.1) 56(84) bytes of data.
64 bytes from localhost (127.0.0.1): icmp_seq=1 ttl=64 time=0.063 ms
64 bytes from localhost (127.0.0.1): icmp_seq=2 ttl=64 time=0.093 ms
64 bytes from localhost (127.0.0.1): icmp_seq=3 ttl=64 time=0.052 ms
--- localhost ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 2000ms
rtt min/avg/max/mdev = 0.052/0.069/0.093/0.018 ms
Test wget To localhost
WGET From URL: http://localhost/nagiosxi/includes/components/ccm/
Running:
/usr/bin/wget http://localhost/nagiosxi/includes/components/ccm/
--2020-04-16 09:17:04-- http://localhost/nagiosxi/includes/components/ccm/
Resolving localhost (localhost)... ::1, 127.0.0.1
Connecting to localhost (localhost)|::1|:80... connected.
HTTP request sent, awaiting response... 302 Found
Location: https://localhost/nagiosxi/ [following]
--2020-04-16 09:17:04-- https://localhost/nagiosxi/
Connecting to localhost (localhost)|::1|:443... connected.
ERROR: cannot verify localhost's certificate, issued by '/C=US/ST=Minnesota/L=St. Paul/O=Nagios Enterprises/OU=Development/CN=10.207.231.149':
Self-signed certificate encountered.
ERROR: certificate common name '10.207.231.149' doesn't match requested host name 'localhost'.
To connect to localhost insecurely, use `--no-check-certificate'.
Network Settings
1: lo: mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: mtu 1500 qdisc mq state UP group default qlen 1000
link/ether fa:4f:39:1e:3e:8a brd ff:ff:ff:ff:ff:ff
inet 10.207.231.149/32 brd 10.207.231.149 scope global noprefixroute eth0
valid_lft forever preferred_lft forever
inet6 fe80::f84f
valid_lft forever preferred_lft forever
default via 10.207.231.1 dev eth0 proto static metric 100
10.207.231.1 dev eth0 proto static scope link metric 100
10.207.231.149 dev eth0 proto kernel scope link src 10.207.231.149 metric 100
Nagios XI Components
actions 2.2.2
alertcloud 1.2.1
alertstream 2.1.1
autodiscovery 2.2.6
backendapiurl 1.0.5
bandwidthreport 1.8.1
bbmap 1.2.1
birdseye 3.2.4
bulkmodifications 2.2.0
capacityplanning 2.3.0
ccm 3.0.5
custom-includes 1.0.5
customlogin 1.0.0
customlogo 1.2.0
deploydashboard 1.3.0
deploynotification 1.3.3
duo 1.0.2
escalationwizard 1.5.1
freevariabletab 1.1.0
globaleventhandler 1.3.0
graphexplorer 2.3.0
helpsystem 2.0.1
highcharts
homepagemod 1.1.11
hypermap 1.2.1
hypermap_replay 1.2.0
latestalerts 1.2.7
ldap_ad_integration 1.1.2
map 1.0.0
massacknowledge 2.2.2
massimmediatecheck 1.0.0
metrics 1.3.3
minemap 1.2.5
msp 1.2.0
mtr 1.0.2
nagiosbpi 2.8.3
nagioscore
nagioscorecfg
nagiosna 1.4.1
nagiosql
nagvis 2.0.4
nocscreen 1.3.2
nrdsconfigmanager 1.6.7
nxti 1.0.3
opscreen 1.8.0
perfdata
pingaction 1.1.2
pnp
profile 1.4.1
proxy 1.1.5
rdp 1.0.5
rename 1.7.0
scheduledbackups 1.2.0
scheduledreporting
similetimeline 1.5.1
snmptrapsender 1.6.2
statusmap 1.0.3
tracerouteaction 1.1.2
twilio 1.0.0
usermacros 1.1.0
xicore
Nagios XI Config Wizards
activedirectory 1.3.4
ec2 1.1.2
s3 1.1.1
java_tomcat 1.1.0
autodiscovery 1.4.2
bpiwizard 1.1.5
bulkhostimport 2.1.2
capacity-planning 1.0.1
dhcp 1.1.6
dnsquery 1.1.5
digitalocean 1.0.2
docker 1.1.1
domain_expiration 1.1.6
email-delivery 2.0.5
esensors_websensor 1.1.6
exchange 1.3.3
ftpserver 1.5.7
folder_watch 1.0.6
genericnetdevice 1.0.4
java_glassfish 1.1.0
google-cloud 1.0.2
hyperv 1.0.2
ibm-i-customsql 1.0.0
ibm-i-service 1.0.0
java_jboss 1.1.0
java_jetty 1.1.0
ldapserver 1.3.4
linode 1.0.2
linux_snmp 1.5.8
linux-server 1.5.8
mssql_database 1.6.4
mssql_query 1.6.6
mssql_server 1.9.2
macosx 1.3.3
mailserver 1.2.6
microsoft-azure 1.0.2
mongodb_database 1.1.4
mongodbserver 1.1.4
mountpoint 1.0.3
mysqlquery 1.2.4
mysqlserver 1.3.4
ncpa 2.2.1
nrpe 1.5.3
nagioslogserver 1.0.1
nna 1.0.6
nagiosxiserver 1.3.2
nagiostats 1.2.3
switch 2.5.2
oraclequery 1.3.8
oracleserverspace 1.5.8
oracletablespace 1.5.9
passivecheck 1.2.5
postgresdb 1.5.4
postgresquery 1.2.4
postgresserver 1.3.5
powerwareups 11-15-2012
printer 1.1.4
radiusserver 2.0.3
rackspace 1.0.2
sla 1.3.4
snmp 1.6.4
snmp_trap 1.5.4
snmpwalk 2.0.0
sshproxy 1.5.8
solaris 1.3.2
tcpudpport 1.3.4
tftp 1.0.3
passiveobject 1.1.3
vmware 1.7.3
watchguard 1.4.6
webtransaction 1.2.6
java_weblogic 1.1.0
website 1.4.1
website_defacement 1.2.1
websiteurl 1.4.0
windowsdesktop 1.6.4
windowseventlog 2.0.0
windowssnmp 1.5.5
windowsserver 1.6.4
windowswmi 2.1.4
Nagios XI Dashlets
alertcloud
bbmap
capacityplanning
graphexplorer
hypermap
latestalerts
metrics
metricsguage
minemap
xicore_xi_news_feed
xicore_getting_started
xicore_admin_tasks
xicore_eventqueue_chart
xicore_component_status
xicore_server_stats
xicore_monitoring_stats
xicore_monitoring_perf
xicore_monitoring_process
xicore_perfdata_chart
xicore_host_status_summary
xicore_service_status_summary
xicore_comments
xicore_hostgroup_status_overview
xicore_hostgroup_status_grid
xicore_servicegroup_status_overview
xicore_servicegroup_status_grid
xicore_hostgroup_status_summary
xicore_servicegroup_status_summary
xicore_available_updates
xicore_network_outages
xicore_network_outages_summary
xicore_network_health
xicore_host_status_tac_summary
xicore_service_status_tac_summary
xicore_feature_status_tac_summary
availability
custom_dashlet 1.0.7
gauges 1.2.2
googlemapdashlet 1.1.0
internettrafficreport
rss_dashlet 1.1.5
sansrisingports 2.0
sla
worldtimeserver 2.0.0