Today, just when starting the working day we have realized that there were somes servers offline (still powered on but without network connection). It seemed that the network adapters were incorrectly configured without the static IPs.
After some research, a job partner discovered that some days ago (March 13th) Microsoft released some security updates that generates issues to Windows 2008 … Read more
Step by step procedure to upgrade an active/standby BIGIP cluster. In this example, I needed to upgrade from BIG IP v188.8.131.52 to v184.108.40.206
Login to https://downloads.f5.com/, search and download the ISO image of the version you want to upgrade to.
As a good sysadmin practice, it is better to export the configuration of both nodes … Read more
The last F5 BIGIP version 220.127.116.11 (I upgraded from v13.0.0 some days ago – 2018 February) seems to generate a bug with the LTM policies.
Fortunately, the issue is only at the Presentation layer. The LTM policy show the rules conditions always with datagroups. This affects all rules and policies.
Better explained with an example:
If this is a … Read more
Last week we published a new application on our web servers (which are balanced by the F5 BIGIP)
Accessing directly to the servers produced no problem, but when the connection was through the virtual balancing IP of the F5, the application did not work correctly.
Fortunately, monitoring the LTM module logs of the F5 (/var/log/ltm) while the problem … Read more
This post explains how to generate self signed certificates with SAN – Subject Alternative Names using openssl. It is a common but not very funny task, only a minute is needed when using this method.
The example below generates a certificate with two SubAltNames: mydomain.com and www.mydomain.com
Create openssl configuration file
Create configuration file for openssh (In a Linux … Read more
It is not the first time my Icinga suddenlty, stops showing the grafana graphs.
If trying to log to Grafana, admin password is not accepted. I am pretty sure i have not changed the password but I am unable to login to Grafana.
And even worse, given that I still have not configured Grafana SMTP section / admin … Read more
Here I am trying to present (I hope in an easy way to understand) some Icinga concepts (maybe also applicable in Nagios) like active and passive checks, enabling and disabling freshness checks, soft and hard states,… and the related parameters to configure them.
ACTIVE and PASSIVE services
There are two types of services:
- ACTIVE: Check initiated by the Icinga
… Read more
I have configured my VSX appliances to perfom scheduled backups every week. Today, my icinga monitoring system has raised an alert informing that VSX2 backup has failed.
GAIA provides some commands to get useful data about the execution of the backup processes.
Show the the latest successful backup
vsx2:0> show backup last-successful
Backup Type: local ( latest )
… Read more
Exim is a very flexible and common MTA (mail transfer agent) in Unix systems.
This posts shows the way to configure Exim as client to send authenticated and encrypted (TLS) emails through a smarthost.
Lets suppose the smarthost email server is listening on port 587 for secure outgoing SMTP…
Configure exim to use the smarthost
To configure exim In … Read more
To configure passive checks in Nagios/icinga I use a tcp listener daemon that launches a script (See Nagios – Using passive checks without agent)
Tried to use inetd superserver daemon, but in the last versions, i have not been able to make it work correctly (See last update in my post: Linux – cannot found / missing inetd.conf)… Read more