IT Blog

Solution for heavy CPU load MikroTik CRS106-1C-5S

One day I was asked to look at MikroTik CRS106-1C-5S, whose users could not use the Internet normally, there was no speed and ping requests dropped out. When I looked at CPU utilization, it was almost 100% (in the menu System – Resources).

Can’t open PID file /run/zabbix/zabbix_server.pid (yet?) after start: No such file or directory

Once, on Ubuntu 18.04.6 LTS, I updated the Zabbix server to version 6.0 LTS and the new version did not start.

Configuring BGP on Juniper MX – traffic balancing

I will give an example of setting up eBGP on Juniper MX204 with several uplinks and balancing traffic between them.

Juniper QSFP Temperature low warning set

One day, after connecting several 40G transceivers to the Juniper QFX5100 and MX204 devices, messages from these devices began to arrive on the syslog server:

How to configure BGP prefix-limit on Juniper

I will give an example of setting up prefix-limit for BGP so that a neighbor does not accidentally send more routes than he should.

Juniper SNMP OIDs DDM for optical signal transceivers

I will give an example of receiving an optical signal via SNMP from optical transceivers connected to Juniper devices.

Juniper MX. How to view user session speed

Let’s say the user has an IP address 172.18.24.33, now let’s see the speed:

Juniper MX. How to send client traffic to a NAT server

Let’s say there is no default route on Juniper MX, or it is not suitable, or client traffic needs to be sent to different NAT servers, in this article I will describe how to do this.

How to change gateway in Linux

Once I needed to change the default gateway on different servers without restarting the network service or rebooting the server, I will give examples of how I did this.

Monitoring Linux directory size in Zabbix

One day I needed to monitor the size of a directory in Zabbix and create a trigger so that Zabbix would notify when the directory size increases.