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.
3,718
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can't ping the WAN IP of a router
I learned to use cisco packet tracer and found something confusing but actually this is not about the cisco packet tracer . I'm curious if this apply in real network as well.
So i tried building this ...
- 113
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Why does only the root bridge send RSTP BPDUs after sync?
From a recent packet capture, after the sync process in RSTP, only the root bridge sends RSTP BPDUs every 'hello' interval. Why is it so?
Shouldn't all switches send BPDUs every 'hello' interval since ...
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Why does RSTP send proposal bit and agreement bit as '1' initially?
From a recent Wireshark capture of a RSTP BPDU on a switch, both proposal and agreement bits were set to '1'.
In my understanding, initially both switches 'propose' themselves as root. The better root ...
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HOW to FC SAN cord compatibility? Cisco FC switch (DS-X9448-768K9) and HP Proliant servers (360 g6, g7, 380 g8), with HP SN1100E 16Gbps HBA
I have obtained a couple of Cisco Fibre Channel switches (DS-X9448-768K9) in the 9700 MDS, which this being my first foray into constructing a SAN with a ZFS FreeBSD server, which I have ebay 'good ...
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256
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Route-map to manipulate metric in EIGRP
I have following Setup
R1 --- R2 --- R3 --- R4 --- R5
The same network is being advertised from R1 and R5. There is some difference in delay between the two paths R1-R2 and R4-R5. So the route from R1 ...
- 1,680
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25
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Can we use cisco MDS 9700 without Fabric Module
We have Cisco MDS 9710 and we want turn it on with 1 I/O module. Is it mandatory to install Fabric Module for it?
My question is , Does MDS 9700 works without Fabric Module or no?
Thanks,
4
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3
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264
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IOS Memory allocation error after ping
I have written a script in Tera Term for a Cisco IR809g which pings 3 different routers(IR 809g) in 2 different networks over the cellular interface. After +- 6 hours I'm getting a Memory allocation ...
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3
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386
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Why does using a /27 bit mask cause an error?
I've been working with the ip 192.168.7.0 / 27 with jump 32, when I wanted to put 96 it no longer works for me and it says that the mask is an error.
192.168.7.96 255.255.255.224
MESSAGE FROM CISCO: ...
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67
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Script Or API way in Cisco ACI to check interface flap statistics
Would you have an option to check all the interfaces that is flapping my fabric ? Please help , i'm 1 Month new to this . Thanks.
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Change AS Number or add new AS number
We want to change the AS number in our RIPE portal and I want to know we should change the AS number in our Cisco router or we can add new AS number with previous configuration?
My current config:
...
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138
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Cisco 2851 Static NAT Entry - Similar Static Entry Already Exists
Thank you in advance.
I have a few 2851 Cisco ISR. This is my NAT Pool config;
ip nat pool NAT-Pool 38.xxx.xxx.193 38.xxx.xxx.206 prefix-length 28
ip nat inside source list 1 pool NAT-Pool overload
...
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83
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IPv4 entries L3 switch
I am preparing the spec for L3 switch. I decided to buy the C9300L series switch, but I found out that the C9300L series has no IPv4 routing table entries. What does that mean? What is the impact of ...
- 13
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snmp mib for monitoring service instance counters
in career ethernet switches like ME3600, we can configure EVC as defined in MEF.
evc counters(service instance counters) are as follow:
rx_green_frames; rx_green_bytes; rx_yellow_frames; ...
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2
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1
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240
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Cisco IOS XE DHCP Starlink - Static route issue
Today i connected the Starlink dish to an Cisco ISO-XE Box (ISR1111) as a secondary wan link and noticed some strange behavior.
I installed a static host-Route to an VPN Tunnel endpoint via
ip route x....
- 497
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1
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276
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NAT not working in cisco packet tracer
Cisco Router Version: 16.7(3r)
Cisco Packet Tracer:8.0 x64
Router(config)#interface dialer 1
Router(config-if)#ip nat?
% Unrecognized command
Router(config-if)#ip nat ?
% Unrecognized command
Router(...
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1
answer
106
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STP Loop issue on long distance link
I have long distance connectivity between west coast to east cost datacenter via our ISP network as you can see that in following diagram (BSN=Boston, PHX=Phoenix)
Now when ISP-A or ISP-B doing any ...
- 4,351
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64
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Update IOS on Cisco CGS2520 Switch
I need to update the IOS on a Cisco CGS2520 Switch. Not stacked, single switch
I have never done this before and I have a couple questions.
I do not have physical access to the switch.
Looking at the ...
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108
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How do I load VLAN database between switches (CISCO 2960)?
I glad for any help on this topic
--
netanel
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261
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Configure password policy on cisco 2520 version 15.2
I have a cisco 2520 version 15.2 out of box today.
I was trying to setup a password policy and no idea how but I managed to lock myself out, did not know about the "reload in X" command ...
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56
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How to configure IPV6 /53 subnet on packet tracer?
I have tried configuring a Ipv6 subnet address 2001:0dce:0000:0000::1/53 into the router interface.
It works but when the I tried setting the auto-configuration button on the PC connected to this ...
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39
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My laptop not comes on the network when connected to cisco 2951 routing port, so it does not ping [closed]
I have assigned 192.168.1.2/24 IP to laptop with 192.168.1.1 gateway. This gateway is actually the IP address of the Cisco 2951 router port. But my laptop doesn't come in the network that's why it ...
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259
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How can I monitor BFD flaps?
We need to monitor BFD flaps on our Cisco Nexus devices but the problem is that Zabbix do SNMP polling every 1 minute, and we can't detect, for example, 5 sec BFD flaps. We detect only if BFD down for ...
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123
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Ramifications of turning off Spanning Tree for EIGRP network?
Ran into something I've never seen before in a production network I'm new to supporting and wanted to get the communities take on it.
I have an EIGRP network that interconnects about 60 sites across a ...
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64
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Client's ARP requests affect whether Cisco C897VA receives packages or not
So I have bought used ISR C897VA with an issue: when vlan1 is pinged from windows there are quite a lot of "Request timed out"s.
Config-register 0x2142 has been done, as well as resetting ...
- 103
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1
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899
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Layer 2 (switch) QoS in a LAN or VLAN-based QoS
In my setup above (Cisco 2960 running IOS15), I have all devices marked in red in vlan 20 (WLAN_VLAN), devices in green in VLAN 10 (PC_VLAN) and devices in yellow which are VoIP in the voice vlan. I ...
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1
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94
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Cisco 887 Conditional Port Forwarding
I have port forwarding configured on a CISCO 887 for client VPN like this:
"ip nat inside source static udp 10.65.1.1 500 interface Loopback1 500"
It forwards them to a VPN server.
However, ...
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5
answers
2k
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BGP <-> OSPF Route Redistribution Loops
In the following topology I have a multi-point redistribution from BGP <-> OSPF and I have recently encountered a routing loop.
After further reading I have understood the problematic routers ...
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Catalyst 3850 password recovery
I think I may have fat fingered the username/password when setting up my Catalyst 3850. I found password recovery instructions. However when I type the command "SWITCH_DISABLE_PASSWORD_RECOVERY=0&...
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99
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SNMPv3 does not show all parameters
I configured SNMPv3 on my Cisco 1841 router. Then I added that router to my monitoring program.
The problem is: it shows only ICMP loss, ICMP ping, ICMP response time and SNMP agent availibility.
It ...
- 203
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607
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Help me understand why to decrease the MTU size
Why I should decrease MTU on interfaces instead of increase it when ipsec encapsulation is present, GRE or some other?
The way I see it: a packet of 1500 bytes comes to the router, then there is IPSEC ...
- 255
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4
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346
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How to add two VLANs for DHCP Pool
Currently one of my customer has DHCP pool created in Cisco Switch and ip address range is 192.168.25.0/24 (This is a VLAN). Now they have 230 devices and They are going to increase device count by ...
- 3,098
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BMP Server on Cisco [closed]
I'm using router Cisco 2900 series with Cisco IOS 15.4(3) M3, and there is no BMP (BGP Monitoring Protocol) configuration. What should I do? What Cisco IOS version that provide BMP?
4
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Traffic sent to GRE Tunnel fails, but GRE Tunnel is up and OSPF adjacencies are formed
NEW INFO_7-12-21
R1#sho ipv6 rout 2001:db8:B2:200::2:2
Routing entry for 2001:db8:B2:200::2:2/128
Known via "static", distance 1, metric 0
Route count is 1/1, share count 0
Routing ...
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2
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1
answer
816
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Unable to disable CRC check on Cisco 2960-X
I have a 48 port Cisco 2960-X running IOS Version 15.0(2)EX5.
I'm trying to connect it to a Ubiquiti EdgeRouter4 using a Ubiquiti DAC Twinax cable..
I'm aware that this is technically not recommended, ...
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64
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How to query which line I am configuring in a Cisco router?
The Cisco router prompt shows only that I am configuring a line: config-line.
How can I make IOS to print exactly which line I am configuring?
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35
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question about local pref and ip transits
I have 3x IP Transits and 2x IXP connected to my router and absolutely we are paying more to IP Transits than IXP so I want to know what is the best local pref can I set for my outbound routes?
my ...
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4
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1
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749
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Cisco IOS -> ASA VTI tunnel not routing traffic
I have a VTI tunnel configured between two devices (ASR and ASAv). The tunnel comes up fine and is stable, however traffic appears to be unidirectional, from the ASR -> ASAv but not in the reverse ...
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1
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358
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Cisco Packet Tracer Hub IP
The problem that I'm facing has to do with the labeling above the hub's. I tried every possible hub in Packet Tracer and none of them had the configuration for IP. My guess is that the IP given is the ...
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3
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1
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70
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Log messages not leaving switch after changing source to management port
I reconfigured some of our switches to add an OOB connection from the management port. The below configuration is from a 4500X, but also seeing this on 3850s and 2960s.
After I did this I updated the ...
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135
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Assigning static IP address from the DHCP pool range on Cisco 800 series
What happens if I assign a static IP address to a device in a LAN where there is an active DHCP server and the address falls within the configured DHCP pool and DHCP server is Cisco 800 Series?
Most ...
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Cisco MAC ACL loop holes
I know this is not a new topic but need to clarify a couple things.
I have a typical office with hosts connected to a Cisco 3560-X in same VLAN.
My goal is to prevent unauthorised hosts ever accessing ...
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1
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65
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DSview 4 Break Sequence
one of our customers is using DSview 4 as a terminal server solution.
I have the problem that I want to send a CTRL+Break to one of our routers.
Unfortunately, I cannot get it to work. I tried CTRL+...
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3
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786
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How to make 2 diffrent networks in router ping each other
Hello i have this 2 routers how i can make them ping each other and alos the devices connected to them
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109
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Meraki and Syslog-NG OSE [closed]
I've been struggling epically to export legible logs from my Meraki devices to a server running Syslog-NG OSE 3.30. No matter what source driver I use on the server, I see errors like this (...
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1
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85
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I cant ping across Lan?
Current configuration : 2695 bytes
!
version 15.1
no service timestamps log datetime msec
no service timestamps debug datetime msec
service password-encryption
!
hostname ...
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136
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VPN/IPsec router support in Packet Tracer
I would like to know, if a router doesn't support VPN (meaning it can't be used as a VPN server) can it still route an IPsec packet?
And which router I should use as a server for IPSec (AH tunnel mode)...
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580
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CISCO PACKET TRACER "INVALID IP ADDRESS"
Hi I am still new and studying about networks have here 234.1.18.6/29 address and mask but when I try it out on Packet tracer it gets me an invalid message. I cannot understand why this address are ...
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0
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40
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iBGP Question reagrding Distribute - List from EIGRP
So, I have the following topology.
A-B
| |
C-D
A-B-C-D are Routers. It doesn't matter what are the IP's of the interfaces. What matters is that I have 2 loopbacks for each router. 1.1.1.1 and 11.11....
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C2960 %LINEPROTO-5 UPDOWN and %LINK-3-UPDOWN when speed is not set on 100
I have 4 ports.
3 are like this, Gi 0/1-3
switchport access vlan xxx
switchport mode access
power inline never
speed 100
spanning-tree portfast edge
One Trunk, Gi 0/8
switchport mode trunk
power ...
- 103
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2
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615
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Are there any differences in features between Cisco ASA hardware appliance and Cisco ASAv appliance
We are planning to replace our existing hardware firewall with new virtual one.
The feature that we require from the virtual firewall is as below:
HTTPS decryption and logging
IPS/IDS
Gateway ...
- 133