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Questions tagged [cisco]

The major provider of networking equipment. This is a generic tag to be used when no more specific tags are available. See the list of tags in Help Center Tag page.

4
votes
2answers
64 views

Nexus 3172T MTU

I am attempting to set the L3 mtu on a Nexus port. The mtu option is only available if I set "no switchport" which then prevents me configuring VLAN related settings. Am I missing something obvious? ...
0
votes
0answers
26 views

VRRP between 2 router on a same switch [on hold]

i have a 2 ccr 1036 (1x 1036 8g 2s+ / 1x 1036 12g 4s) both of them are connected to my datacenter provider core switch and both of them are connected to same core switch in my network ( i have core ...
0
votes
1answer
26 views

Importance of DHCP option 12, client host name

The main purpose of a DHCP server is to provide dynamic configuration for a group of hosts (mainly IP, Gateway and DNS). There are several options that can also be sent. Option 12 (client hostname), ...
0
votes
0answers
22 views

Nexus 3K doesn't prompt to change password [on hold]

I'm working on Nexus 3K(3048, 3524) and several C6500 devices. They are all using TACACS+, and have to change password every 90 days. Today, I was tried to login Nexus 3K, and keep fails to login. So,...
0
votes
0answers
20 views

Problem in NAT Outside configuration [closed]

im learning networking in my course. i followed NAT course in this site NAT PROBLEM . i did the setup as in the diagram then setup the NAT on R2 as mentioned in the page. I didn't do routing because ...
-1
votes
0answers
11 views

I need this solution VLSM topology HELP [closed]

Let you are a network administrator of an online sales company. You have already decided the number of host requirements for different sections. Host requirements for different sections are: WAN ...
0
votes
0answers
6 views

Does a pod in kubernetes correspond to an EC2 instance in Amazon? [closed]

I'm trying to get up to scratch on this projct I'm staffed on during my internship, and I'm trying to better undertand what a pod is. It seems to correspond to an EC2 instance as is in AWS? A ...
0
votes
1answer
29 views

Login local , login synchronous

I dont understand what those two comands mean when im enabling ssh on Vty-line. Can someone please explaim me please whatthose comand do and why i need to use them?
1
vote
1answer
134 views

Extremely long time to establish network link with Nexus N9K-C9372-PX-E

This switch is completely default, no configuration has been done other than resetting it to default configuration, and going through the normal naming of the switch and time etc. The problem I'm ...
0
votes
0answers
56 views

Cisco QoS Queuing models

I would have a question about the Cisco Queuing models. For example, when we speak about 1p7q3t, or 2p6q3t, or others models, does it from hardware or software considerations ? If it's hardware, if ...
0
votes
1answer
24 views

Connectivity from DHCP-based machines to servers with static IP addresses on the same gateway

I have Comcast service with 5 static IP addresses, using a Cisco DPC3939B as the cable modem. In addition to the 5 machines with static IP addresses, there are additional devices that get their IP ...
0
votes
0answers
24 views

Clean my Cisco Catalyst 3750 running-config of a `macro global` mess

Relatively new to IOS here and once I got ssh configured I began using scp to get/put my running-config from a Git repo I made to track my changes. When I first acquired the switch (used) I had used ...
5
votes
2answers
295 views

Cisco show log number of messages

When I run the "show log" command, it displays the latest 360 messages. Why 360? Can this value by changed? If yes, what is the command for that? Thanks.
3
votes
2answers
328 views

can we use Cisco 4900M switch for converting single mode (1G) to multi mode (10G) interface

can we use Cisco 4900M switch for converting single mode (1G) to multi mode (10G) interface. Please let me know other possible solutions.
1
vote
1answer
25 views

Why do Cisco IOS switches send packets to DHCP servers with zero giaddr field when DHCP snooping is on?

I recently troubleshooted a network where the switch had DHCP snooping turned on and even though the router which was acting as a DHCP server was connected to a trusted port, the client wasn't able to ...
1
vote
1answer
43 views

hsrp on both side of router

i tried to create a simple network topology to test the Hot standby router protocol gateway for "server2" and "server3", and the architecture is shown in the figure below. i would like to clarify ...
3
votes
1answer
39 views

Cisco Nexus 5548 802.1x Guest-VLAN not available

I'm trying to configure a Cisco Nexus 5548 for 802.1x using MAC Authentication Bypass. I'm finding that there isn't an option to configure the guest VLAN in the event that authentication fails. ...
-1
votes
0answers
15 views

how to calculate the smallest possible list of Supernets? [duplicate]

2- The ISP Company has IPv4 addresses 193.6.128.0/21, 193.6.132.0/21 and 193.6.145.0/24. Because of the address sparing requirement, the company applies superneting mechanism. Calculate the smallest ...
-1
votes
0answers
19 views

What is the relationship between these numbers, how do I derive these IPs? [duplicate]

How do I derive the following IPs / what is the relationship between them? I'm 99% sure I can understand the answer if someone just throws the right keyword at me. I haven't done networking in a while ...
3
votes
1answer
29 views

Ability to monitor all broadcast domains

Example: Network of company A has 5 VLANs: Accounting, IT, Guests, Servers, Board. All VLANs has DHCP servers enabled in their own VLANs. I am monitoring a single VLAN for DHCP packets by connecting ...
2
votes
0answers
24 views

Cisco ASA Dial in VPN access Devices on Site-to-Site VPN

Questions 1) What do I need to run to get this to allow the on-site to talk to the dial-in network clients E.G ping from 10.101.1.7 to 10.101.2.1? 2) What do I need to run to get the dial-in network ...
2
votes
2answers
455 views

How many pps (64Byte each) i can receive in 1Gbps throughput modem / firewall

I need help with this: If i have 1Gb/s throughput. I can receive how many pps in 64Byte each packet / s? Let's say I can send (Packet / Second - 64Byte) 450,000, meaning I would not only have 230.4 ...
1
vote
1answer
76 views

BGP Juniper not reflecting to Cisco?

I am really new to working with Junipers and I am struggling a bit with Route Reflector configuration. I have 3 routers Cisco-Juniper-Juniper2 here is my config: Cisco: router bgp 100 neighbor ...
0
votes
1answer
36 views

EIGRP not working

Three routers are connected to a main switch in the middle. I configured the Routers with 3 separate network ID's 192.168.30.0, 192.168.20.0 and 192.168.10.0 and there /24. I created the EIGRP and ...
4
votes
1answer
43 views

set cli complete-on-space Cisco equivalent

Does anyone know what would be the equivalent, if any, of the Juniper command 'set cli complete-on-space' for Cisco? I used to work with Juniper devices and I LOVED this feature, but now we are ...
6
votes
1answer
36 views

Two boot system images in cisco router

on my router I have two boot lines: boot-start-marker boot system flash c1900-universalk9-mz.SPA.157-3.M3.bin boot system usbflash0:c1900-universalk9-mz.SPA.157-3.M3.bin boot-end-marker I have a ...
-1
votes
0answers
18 views

Why can't I ping other spoke in hub-and-spoke frame relay with exit interface as default gateway?

I have the following topology configured, where R1 is the hub and R2 and R3 are spokes: The frame relay configurations are: R1: R1#sh run | s Serial1/0 interface Serial1/0 no ip address ...
2
votes
1answer
45 views

If traceroute fails why does ping still work?

If I can ping a router successfully, why is it that when I do traceroute, it stops at a particular interface and says "ICMP type:3, code:3, Destination port unreachable". Doesn't that mean that it can'...
2
votes
1answer
25 views

Need help to replicate the results of a tutorial on Frame Relay Configuration on Router. What do I need to change/add?

I'm having trouble getting the output shown at 03:14 here: Frame Relay configuration by Kevin Wallace My Network is 3 routers, each connected to the frame relay switch via Serial2/0 interface, with ...
2
votes
2answers
78 views

Is “Host unreachable” the same as “Communication administratively prohibited” in Access List ping response?

Below is a portion of my topology. Faculty of Arts student subnet should not be able to ping Faculty of Arts staff subnet but the staff should be able to ping the student subnet. I know that this ...
2
votes
1answer
80 views

How to make PCs in the same LAN but on different networks communicate

Is it possible to ping PCs in the same LAN but on different networks? I've done RIP version 2 on all the routers. They all can ping each other. However, the PCs cannot. For example, when I try to ping ...
0
votes
1answer
14 views

Cisco ASA 5506 log collection after power cycle

Today we had to power cycle our Cisco ASA 5506 , since I could not connect to it through any of the connected interfaces. How can I get the logs to see what failed or what was the state of the ASA ...
2
votes
1answer
39 views

4507r Supervisor engines aren't operating redundantly

The tl;dr : I have two supervisor engines in a 4507r but the standby unit doesn't appear to be ready to perform when the active module dies. On Sunday I had a network problem that appeared to be ISP ...
1
vote
1answer
31 views

IP Routing question

We are in the process of replacing our firewall and are keeping the VPN client traffic on the older device. The public IP range is being split between the two devices from our border router. All the ...
-1
votes
0answers
9 views

integration extreme switch to cisco ise

i hope you are doing well please can you help to see if the error it's in the switch extreme or in the ise? im getting the following error from ise Event 5400 Authentication failed Failure Reason ...
3
votes
3answers
85 views

Cisco ASA logging to remote syslog question

I have Cisco ASA and i have setup graylog logging server and i am seeing no logs coming on remote syslog so this is what i did.. Current config: asa-fw1-010101-2-7/pri/act(config)# show run logging ...
2
votes
3answers
48 views

connect a cisco router to the internet through a cable modem

The router gets an External IP address via DHCP from the Cable modem Clients inside the network get an IP address from Router's DHCP server I can ping that the external IP address from a client inside ...
2
votes
0answers
26 views

DHCP ivp6 vs DHCP ipv4 router config (cisco)

When setting up a router as dchp server in ipv4, we specify a pool under which we give the network and the default-gateway and that's it: However in ipv6 stateless dhcp , we create the pool then ...
0
votes
1answer
62 views

WAN/Campus network design - Learning purposes

I am trying to build a WAN connecting various LAN's via frame-relay for learning purposes, i do not have that much experience with frame-relay or network design (mainly creating LAN's and connecting ...
1
vote
1answer
33 views

Cisco/Meraki switch SFP compatibility and dual link

Our company wants to connect two different floors together about 150-200 feet apart. I was thinking fiber would be the best option for this but I don't have much experience so I would like to see if ...
0
votes
1answer
59 views

Switch cannot ping server

My switch won't ping my server. Both are directly connected with each other, and are in vlan 666. When I initiate a ping from my switch to my server, the switch sends ARP requests. Then the server ...
2
votes
1answer
130 views

QOS police vs bandwidth - is this configuration wrong?

I understand bandwidth in QOS is use to guarantee a minimum bandwidth I understand police in QOS is to set a limit to the maximum bandwidth. class test_out police **1608000** 50000 100000 conform-...
3
votes
1answer
32 views

security benefits of using RADIUS in router authentication - packet tracer

I'm trying to learn how can one protect routers (using Cisco Packet Tracer) and I found out I can set local password to authenticate access to the router privileged and configuration mode. However, I ...
2
votes
1answer
27 views

QSFP BiDi 40GB with two LC-LC

This Cisco module QSFP-40G-SR-BD is Bi-Directional (BiDi) 40Gbps QSFP, which means a single link used for RX & TX, each link 20Gbps, two LC links in total gives 40Gbps connection. If we will use ...
1
vote
0answers
62 views

OSPF over IPIP tunnel doesn't work for CSR 1000v in AWS

I literally have the following topology shown in the figure below. I have 4 VPCs, each VPC has 3 subnets (1 for the VM instance and the other 2 for interfaces). Each VPC hosts a Cisco CSR 1000v in ...
4
votes
1answer
65 views

Does QSFP+ require 4 fibers?

I am currently designing a network, and there are 2 fibers between 2 switches. Can I use a 40Gbit QSFP+ module to achieve this speed or is 10Gbit SFP the best possible without adding more fibers?
0
votes
1answer
21 views

i cant configure the ip adress and subnetmask ,i only have one router “1941” and 2 pc's

the command line is this : Router0(config-if)#ip adress 192.168.1.1 255.255.255.0 the error message is : % Invalid input detected at '^' marker.
0
votes
0answers
24 views

100G Links and Equipment

I am interested in migrating from 10G to 100G and i started to look for some switches. I have read about N3K 3232C and a N9504. I know they are from different families...but the reason is that one of ...
2
votes
2answers
89 views

IPv6 can't ping host when static route configured with exit interface

I have the following topology (using IPv6) interfaces: I have the following static routes configured on it: R1#sh ipv6 route static IPv6 Routing Table - default - 9 entries Codes: C - Connected, L -...
0
votes
1answer
40 views

How to create interfaces for CSR 1000v for GRE tunnels?

Well, my idea is to connect to 4 CSR 1000v routers in different VPC (without VPC peering). I've basically finished with everything with the pre-configuration creating VPCs, subnets IGW, modifying ...