Learning IOS and JUNOS

As everyone knows that OSPFv2 is a standard routing protocol (http://www.ietf.org/rfc/rfc2328.txt), but not all vendors device will implement it exactly the same. Especially when the network scenario was not follow the standard design, then it might have different exceptional behavior in different vendor devices. In order to compare the difference behavior between Cisco and Juniper. I designed a special OSPF topology just like below, so we can see Cisco and Juniper have different result of routing exchange behavior.

A bird in the hand is worth two in the bush Day 3 - How to view or modify JUNOS configuration ? Entering Configuration Mode When you stand behind an engineer, you can identify the engineer is Cisco or Juniper guy easily.  Most cisco engineers like to use the command 'conf t' to enter configure mode of router or switch. router>  enable Password: router#  conf t Enter configuration commands, one per line.  End with CNTL/Z. router(config)# When you want to show any results, you don't need to exit to the privilege mode(#) to show it. You can leverage 'do' command to check the status. router(config)#  do sh ip int brief Interface              IP-Address      OK? Method Status                Protocol GigabitEthernet1       10.17.14.195    YES manual up                    up ...

Junos Script Automation is a powerful and flexible on-box toolset which provides customization of network behavior, adaption to what your application expects to configure, manage and diagnose if and when needed. It sits right above the Junos OS, with a northbound interface to Junos Space applications, and southbound access to Junos SDK applications and native management plane instrumentation. This customized programmable solution makes your application smarter and better in real-time. In Juniper official website provides many script samples to match part of common requests. In my company, we deployed many inter-connections EBGP/IBGP between router or layer 3 switch. So I picked one op script from the JUNOS Script Library - show bgp policy : display all routing-policies in sequential order for a selected BGP peer.

Configuration Management Day 2 - How to review router configuration ? In Cisco IOS, it has two default configuration files:  (1) startup-config: is used for initialization of router boot up process   (2) running-config.  is the real-time concurrent configuration repository whenever you type any commands in IOS. And how do you differentiate screen output is the startup-config or running-config ?

Once a use, forever a custom My first-time experience of Cisco router installation was in 1997, when I was a junior network engineer in a small company. I remembered that day I finished installing a customer router on-site for only 15 mins then I left and went back again after 2 hours to configure the router via console again..because I forgot to configure password under line vty (I told myslef I would never made such stupid mistake again like that - Password required, but none set ) After 13 years later, I started to learn JUNOS since 2010. Because I familiar Cisco IOS so much, so I knew the feeling of use behavior change from IOS to JUNOS. The hierarchical structure is not so easy to read when you see it in the first time.(especially when you have no any programming experience) However, having the use experience of Cisco IOS is a not a bad thing before you start to learn JUNOS. I believe if you can leverage your previously IOS command knowledge then map to JUNOS relative s...

In order to prepare the future migration from Juniper SSG to SRX, so I tried to use SRX GUI interface to see how its easy for operation team to sustain this. This is the first time I tried to use GUI to manage a router, and if you are not familiar with Juniper SRX features and functions, I have to say its a quick start to have a glance overview of Juniper SRX by web interface. For many junior engineers, if they can have what-you-see-what-you-get interface, they will accept new technology as fast as they can or they might refuse to try or to learn new technology if there's no time pressure or instructions from high-level managers directly . We are still using CLI to control most routing and switching network device today, but I believe someday the condition may change if the network virtualization come true.(I think no one would like to control firewall by CLI, isn't it ?)

Juniper CLI learning is a little challenge for junior network engineers or Cisco IOS engineers, because the JUNOS modular and hierarchical structure design. Some features may need several command line which were configured under different hierarchical levels, then combined all of them together in another hierarchical level. Such kind of CLI design especially not easy to learn when apply CoS on juniper device.(I believe many Cisco IOS engineers don't want to switch to JUNOS because of this...) As above figure is my understanding about the related JUNOS command which is using in our production network.

Olive Introduction for TOI from Johnson Liu

有時候想偷懶，懶得用FTP把JUNOS上傳到Branch SRX(SRX100/SRX200...)上；或是在機房裏真的忘了某一台設備的IP，懶得再走回座位去查，如果可以像以前M/T-Series直接用USB昇級JUNOS的話就可以省去許多的麻煩。 我以前曾經在JUNOS 10.2上嘗試過許多次都不成功，後來看到Juniper Learning Portal的教學才知道原來跟SRX本身的版本也有關係，至少要10.4以上才能支援USB自動昇級的功能。 步驟如下： 1. 先拿個USB隨身碟格式化成FAT/FAT32格式 2. 將要昇級的JUNOS版本(我是用複製到USB隨身碟中根目錄下 3. 執行這個指令 C:\> echo ""> [USB隨身碟的磁碟代號] :\autoinstall.conf EX: 我的USB隨身碟是F Drive，所以我的指令是 C:\> echo ""> F :\autoinstall.conf 4. 把USB隨身碟插到SRX的USB slot中，接著稍待片刻讓SRX偵測到USB 以下是我現有的版本  [edit] root# run show version Model: srx100h JUNOS Software Release [10.4R6.5] 當你插入USB時，Console會出現類似以下的提示  [edit] root# umass1: Unigen Corporation PQS1000B1, rev 2.00/11.00, addr 4 da1 at umass-sim1 bus 1 target 0 lun 0 da1: Removable Direct Access SCSI-0 device da1: 40.000MB/s transfers da1: 980MB (2007040 512 byte sectors: 64H 32S/T 980C) FSTYPE = 11...(omit)   5. 直接按下SRX的RESET CONFIG按鈕(注意不要按錯POWER按鈕) 6. 接下來所有的燈號都會變橙色燈號，然後就開始自動進行昇級動作；昇級完成會自動重新開機，開機完成後重新登入就看到新...