• 2021-04-19
  • 2021-04-19
  • 0件

List and how ” | ” pipeline commands for Cisco devices

Do you know the “| pipeline”, a command technique that should be used by those who manage and set up Cisco devices?? It is a basic skill among network engineers who use Cisco devices, but many front-end engineers who do not usually touch the equipment do not know. You can use this pipeline to display only some of the lengthy commands that are output in the CLI. I often use the show run command, but most of the output is unnecessary, isn’t it? About | ” command Read “|” ← pipeline First of all, you don’t know how to read this symbol. smile It is called a “pipe” or “pipeline”. I often don’t know how to call it and can’t tell my customers and partners by mouth. How to 「|」 Type the command that is provided after < a0>, and then type any string.</a0> This “|” Searches for strings in the output of commands entered before < a0>, and changes the output. </a0> (Since it is difficult to understand, the following is an example.) ) For example, in the example above, you can use the “show run” |” I’m using . 「|」 is followed by “inc” (include) and the string […]

  • 2021-04-05
  • 2021-04-05
  • 0件

Be careful with meraki MR’s L3 firewall settings

Meraki, a cloud-managed network device that is one of the Cisco products, has attracted a lot of attention in recent years! It is also very easy to set up, manage, and become a very convenient and popular product in remote work environments. In addition, it is very speedy at the time of introduction, and it can be used simply by connecting Meraki to a port that is connected to the Internet. It is a very favorite product among me! Therefore, I will introduce the MR series “Default setting of firewall function” that I met many times in various environments in the author. About meraki MR series firewalls About features The Meraki MR series is an access point, but a firewall function is implemented. There is a “firewall”, but it is not a function like UTM, but “access list (ACL)” of layer 3 and layer 7. (*Adult content filtering is possible in NAT mode.) ) Layer 3-level ACLs allow you to specify transport protocols (UDP, TCP, ICMP), destination IP addresses (segments), and destination port numbers, allowing/blocking radio client traffic as it crosses mr uplinks. Note) Cisco devices basically have ALL Deny set on the last line, while Meraki MR has ALL […]

  • 2021-04-04
  • 2021-04-04
  • 0件

Operation by ACL “Packet generated by the router itself”

Cisco qualified CCNA and CCNP frequently have access list (ACL) issues. Or y, it is always asked. Among them, there is content that the examinee often mistakes, and there is a content that “can not be solved undying if you do not know it”. The content is “Packets generated by the router itself are not subject to the access list”. Let’s test if the packet is actually uncontrolled. Test configuration Configuration/Settings Set the following access list to Cisco 891fj and Ping another router with ip address 192.168.55.1. * By the way, it is necessary to set protocol settings and destinations, so use extended ACLs. The access list 100 specifies a protocol ICMP, and the source is Any (all), and the destination is set to 192.168.55.1. Then set the access list 100 to the out direction (egress) of GigabitEhternet8 on the orange router. This should control ICMP packets from the orange router to 192.168.55.1. Router#show run int gi8 interface GigabitEthernet8 ip address 192.168.55.80 255.255.255.0 ip access-group 100 out duplex auto speed auto Router#show access-lists | sec 100 Extended IP access list 100    10 deny icmp any host 192.168.55.1 Since “implicit Deni ALL” is set to the last line, all resulting […]

  • 2021-04-04
  • 2021-04-04
  • 2件

How to find a list of Cisco Wireless features for each product/OS

Cisco’s Wireless products have two types of operating systems, such as AyreOS and IOS XE, and there are various forms of management in which the Cisco00 series and catalyst series exist and are deployed in the Wireless Lan Controller (WLC). Ap modes include Autonomous, Lightweight, CME, and EWC, which are very complex to deploy. Of course, “difference” is also born in functions that can be used in different ap modes, OS, etc. To be honest, I want you to unify. I think that it is to be able to introduce / propose flexibly to various environments. You can easily check the list of functions by these modes and operating systems in “Feature Matrix” published by Cisco. Feature Matrix for Access Point Let’s take a < at The Feature Matrix for Wave 2 and 802.11ax (Wi-Fi 6) Access points > cisco official website. How do you see it? From “Table of Contents”, you can first scroll to the list of functions by clicking on the OS and mode you plan to introduce/use. For example, if you are using FlexConnect mode in Lightweight, see FlexConnect Feature Matrix (AspireOS). The left column “Features” contains common wireless and Cisco function names, and yes or […]

  • 2021-04-03
  • 2021-04-04
  • 0件

[350-401]Difference between FIB andRIB part.1

Question Which of the following is correct about the difference between RIB and FIB? Fib is based on THERIB. Rib maintains fib mirror image. RIB is used to determine switching based on ip source prefix. The FIB stores all IP routing information. See answers (1) Commentary FIB(Forwarding Information Base) A FIB is a table that contains the transfer information generated when the device has enabled the switching mechanism Cisco Express Forwarding (CEF). A FIB contains a prefix from an IP routing table or global RIB that is structured in a way that is optimized for forwarding. When routing or topology changes occur on the network, the IP routing table is updated and these changes are reflected in the FIB. The FIB holds the next-hop address information based on the information in the IP routing table. RIB(Routing Information Base) A central repository of routes containing L3 reachability information and source IP addresses or prefixes. RIB is also known as a routing table. <参考>https://www.cisco.com/c/ja_jp/td/docs/cian/ios/ios15-1s/cg/013/isw-15-1s-cg/cef-overview.html#16041</参考>

  • 2021-04-03
  • 2021-04-04
  • 0件

Cisco AP not powered by 802.3at from PoE switch

One of the requirements when introducing a wireless access point (AP) is “power supply”, isn’t it? There are many factors that must be considered, such as the amount of power supplied to the AP and the power supply method. If they are not met, the wireless transmission power will be insufficient and the cell range will be reduced, or the usable frequency band will be limited. There are various effects such as being done. So I connected the Cisco Catalyst 9120 Series to a PoE switch that could power at 802.3at (PoE +) in my previous environment, but for some reason it didn’t power at 802.3at. I will write about this including the cause element. Wireless AP is not powered at 802.3at. Matter I connected the AP (Catalyst 9120) to a switch (Catalyst 9200) that can supply power to PoE, but there was a phenomenon that power was not supplied at 802.3at (PoE +). Since the model of Catalyst 9200 has a model number that can be powered by PoE +, it is possible to secure a budget of up to 30 W with one port. Therefore, you can receive a maximum of 25.5W of power to the AP side […]

  • 2021-03-29
  • 2021-04-04
  • 0件

[350-401]Cisco EtherChannel PAgP Mode Combination

Question Which of the following combinations of PAgP modes prevents etherChannel from forming? auto/desirable desirable/desirable desiravle/auto auto/auto See answers (4) Commentary Combination of EtherChannel (PAgP) operating modes Cisco’s proprietary EtherChannel negotiation mechanism PAgP has two modes to set up the interface. Desirable Enable PAgP unconditionally. Start sending negotiation messages to other ports. Auto Enable PAgP only when a PAgP device is detected. In other words, it waits for an on-the-other request and responds to a request for PAgP negotiation. This reduces the transmission of PAgP packets. Auto and Auto do not start negotiating PAgP from the above mode. A combination of Desirable/Desirable and Desirable/Auto is required to use PAgP. Therefore, the combination that prevents formation is ④.

  • 2021-03-25
  • 2021-04-04
  • 0件

[350-401] Difference between FIB and RIB part.1

Question Which of the following is correct about the difference between RIB and FIB? FIB creates data based on RIB. RIB maintains the mirror image of FIB. The RIB is used to make a switch decision based on the IP source prefix. All IP routing information is stored in the FIB.   See Answer ①   Commentary FIB(Forwarding Information Base) FIB is a table that stores transfer information generated when the switching mechanism CEF (Cisco Express Forwarding) is enabled on the device. The FIB contains prefixes from IP routing tables or global RIBs that are structured in a way that is optimized for forwarding. When a routing or topology change occurs in the network, the IP routing table is updated and these changes are reflected in his FIB. The FIB holds the next hop address information based on the information in the IP routing table. RIB(Routing Information Base) A central repository for routes containing L3 reachability information and source IP addresses or prefixes. RIB is also known as the routing table. <reference>https://www.cisco.com/c/ja_jp/td/docs/cian/ios/ios15-1s/cg/013/isw-15-1s-cg/cef-overview.html#16041

  • 2021-03-17
  • 2021-04-04
  • 0件

[350-401]Exclusive control by Python script

Question The network administrator has prepared a Python script to configure a network device running based on IOS XE. The administrator is worried that a colleague will make configuration changes to the device while the script is running. What is the Client Manager action to prevent colleagues from making changes to the device while the script is running? m.lock (config = ‘running’) m.lock (target = ‘running’) m.freeze (config = ‘running’) m.freeze (target = ‘running’) See Answer ②   Commentary Python lock() object It is a Python object used for exclusive control when performing parallel processing. Specify the specified resource in () and control (block) the process when the executed work / command matches. <reference>Python Documentation (threading) IOS NETCONF target /config/ Resources in the NETCONF configuration store <rpc message-id="101" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"> <lock> <target> <running/> </target> </lock> </rpc> <reference> Cisco Programmability Guide

  • 2021-03-16
  • 2021-04-04
  • 0件

[350-401]Exclusive control with Python scripts

Question Network administrators are preparing Python scripts to set up network devices running ONS XE-based. Administrators are concerned about coworkers changing settings on their devices while the script is running. What is the client manager’s action to prevent colleagues from make changes to the device while the script is running? m.lock (config = ‘running’) m.lock (target = ‘running’) m.freeze (config = ‘running’) m.freeze (target = ‘running’) See answers (2) Commentary Python lock() object It is a Python object used for exclusive control when parallel processing. () specifies the specified resource and controls (blocks) the processing if the work/command performed matches. <参考>Python Documentation (threading)</参考> IOS NETCONF target /config/ Resources in the NETCONF Configuration Store <rpc message-id="101" xmlns="urn:ietf:params:xml:ns:netconf:base:1.0"> <lock> <target> <running/> </target> </lock> </rpc> <参考> Cisco Programmability Guide</参考>