Watch interface speed in Linux

watch -n 1 -d ifconfig eth0

Nagios NRPE disk not accessible

While adding NRPE service on host for monitoring, there might be such error on Nagios.

DISK CRITICAL – /dev/mapper/vg-var is not accessible: No such file or directory 

Resolution on host:

sudo vi /etc/nagios/nrpe.cfg

modify for:

command[check_varlog]=/usr/lib64/nagios/plugins/check_disk -w 10% -c 5% -p /var/log

Red Hat – autostart service on boot / Wildfly

example with Wildfly

[Unit]
Description=The WildFly Application Server
After=syslog.target network.target
Before=httpd.service

[Service]
Environment=LAUNCH_JBOSS_IN_BACKGROUND=1
EnvironmentFile=/etc/wildfly/wildfly.conf
User=wildfly
LimitNOFILE=102642
PIDFile=/var/run/wildfly/wildfly.pid
ExecStart=/opt/wildfly/bin/launch.sh $WILDFLY_MODE $WILDFLY_CONFIG $WILDFLY_BIND
StandardError=syslog
SyslogIdentifier=wildflyserver

[Install]
WantedBy=multi-user.target

linux change password & account expiration date

chage -m 7 (min days) -M 60 (max days) -I -1 -E -1 <user_login>

verify:

chage -l <user_login>

remove user account expiry date
chage -E -1 login

set password date change
chage -d 2023-02-15 login