Wassim

I had the opportunity to participate in an official Juniper Networks course titled “Configuring Juniper Networks Routers”, aka CJNR. My boss was kind enough to ask my client to give me five days off. Our instructor was JNCIP certified and works at Twine Networks . All I can say is that 5 days aren’t enough. Juniper Networks should reconsider the necessary time for the CJNR course. There is a lot of knowledge to cover. Labs take a considerable amount of time if you want to assimilate the steps and not only do the secretary work of reading the manual and typing the instructions as shown. For example, we didn’t cover the multicast course as we ran out of time. Topics like BGP, routing policies, multicast and firewall filters on JUNOS sounded like “Chinese English” to me.

import = receive into routing table export = send to neighbors, or, redistribute (or not).OSPF —— Default import policy: accept all OSPF routes from neighbors Default export policy: advertise all direct routes (including loopback interfaces).Here’s an example to illustrate it. Dubai learned the 15.15.15.15/32 route through OSPF from Tokyo. In fact, the default export policy in Tokyo is to advertise its direct routes, one of which is 15.15.15.15/32. The default export policy on Dubai is to export all direct routes. Then MontReal learned 15.15.15.15/32 from Dubai, because the default import policy is to accept any OSPF routes. Wait a minute, 15.15.15.15/32 is not a direct route in Dubai. So how does Dubai advertise it to MontReal? I found the answer to it in JUNOS Enterprise Routing book. It says : “ The default LS export policy is to reject everything. LSA flooding is not affected by export policy, and it is used to convey routing in an indirect manner in an LS pr...

Building a Juniper olive lab and playing with it is no different than gathering Cisco OS images and stuffing them into GNS3 or eve-ng. This articles describes some of my ramblings. As you know, in order to play with Juniper Junos in a lab, you need to configure instances of Olive. In my home lab, I have configured 6 Juniper Olives to play with. This is an overkill for JNCIA and JNCIS. But I got hooked on this topic for a couple of days. I remember waking up and labbing at 4.20 am building Olives LOL. Maybe my motivation behind that is that I wanted to practice every Junos topic on the exam guide as quickly as possible. So here’s the topology of my first Juniper home lab: Candidate Configuration vs Active configuration in Junos Let’s check show configuration interfaces on the operational mode: We have the same output with “show interfaces” under [edit interfaces] level: Let’s make a little change under interface tap (I added a description ): Now, if we issu...