Recent Posts

Juniper Direct vs Local Routes

Juniper routers consider a directly configured IP as a “local” route, except when you use /32 mask. Then it is a “direct” route. This caused me some confusion when creating...

Juniper Default ARP Policer

Juniper devices have a default ARP policer that drops ARP requests and responses over 150kbps. By default, this is an aggregate policer that applies to all interfaces. This can lead...

Juniper Branch SRX LACP Weirdness

Juniper SRX 300 Series firewalls may stop forwarding traffic in some situations. The firewall says it is forwarding the traffic, but it doesn’t work. Monitoring traffic looks OK, ARP entries...

Juniper QFX10K IPFIX Gotchas

IPFIX is problematic on the Juniper QFX10K switches. Documentation is sparse, and doesn’t have a complete configuration. Behavior changes between versions in undocumented ways. Here’s a couple of things I...

Juniper MX Upgrades Causing Overheating

Juniper changed the way they do temperature management on MX240 and MX480 chassis devices, somewhere between 15.1 and 17.3. The net result is that your chassis might run hotter after...

QFX Upgrades - Check Host Version

I came across a situation where a software upgrade failed for some members in a Juniper QFX Virtual Chassis. There is a known issue with upgrades with a certain configuration...

Junos SNMP via Routing Instance

Juniper routing instances are very useful when you need separate routing tables on the one device, for example to separate customers. Junos lets you configure SNMP polling of routing instances,...

New Role with Valve

I have started a new role as a Network Engineer with Valve Corporation. My period of unemployment was short-lived, and I am gainfully employed once more.

Netlify Migration

This blog is now hosted via Netlify, rather than GitHub Pages. It is still built using Jekyll, but I updated the theme to Mediumish.

CCIE Renewed Once More - Exam 400-101 v5.1

I’ve given in to the Sunk Cost Fallacy once more: I’ve renewed my CCIE. There was a lot of foot dragging this time around, and I only had four months...

CLI Still Sucks for Automation

Using network CLI for automation has always been fragile. But it keeps surprising me with the way it breaks. This time, it was a combination of Ansible, Arista, replace: config...

Our Green Card Journey

We are now Lawful Permanent Residents of the United States - aka Green Card Holders. It took a few years to get to this point. Here’s our timeline, why we...