Questions tagged [cisco-ios]
For discussion about Cisco's Internetwork Operating System - Cisco IOS
574
questions
1
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0
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24
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Set promiscuous port for upstream LACP trunk on Cisco 2960X
I have a series of clients who are looking into a intra-VLAN isolation scheme to satisfy a DDQ request.
I was looking into deploying private VLANs for all client device / voice VLANs to satisfy this ...
- 11
0
votes
1
answer
23
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Unable to configure Site to Site VPN between Cisco Router & Cisco ASA and permit SSH
I am performing configuration on Cisco ASA and Cisco Router from the packet tracer. I am attempting to allow the external network (172.16.22.100 255.255.255.0) to access the internal server which is ...
0
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0
answers
27
views
Cisco switch ios update without change license
I need the following ios switches to be updated to the latest "license-free" version to fix vulnerabilities:
C3560CX-12pd-S
C3650-48PS-E
C3850-12S-E
C3850-24T-E
C3850-12S
I didn't find any ...
0
votes
0
answers
42
views
Using ACR (adaptive clock recovery) across pseudowire
I am using back to back Cisco 2941s (mwr2941-adviprank9-mz.151-3.MRA3) in the lab to attempt to establish a pseudowire circuit for T1 delivery. I am trying to establish timing by using adaptive clock ...
0
votes
1
answer
27
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Does this DHCP Server need a trusted ARP Inspection port in IOS?
The switch runs Cisco IOS. You want to configure security on Switch 1. The objective is configuring Dynamic ARP Inspection on Switch 1. Which Ports or port will you configure as Trusted?
A) None of ...
0
votes
1
answer
96
views
Will an OSPF route in IOS be preferred over a static route? (It isn't Floating Static)
For the network topology attached in the image, a static route is configured with ip route 10.10.10.0 255.255.255.252 Ethernet0/0. Referring to the Topology and the output from the show ip route ...
1
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1
answer
171
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Cisco port channel identification through SNMP
on a cisco switch is there any way to identify, through SNMP queries, which interfaces are involved and configured in a port channel?
I did some experiment with commons MIB, without result.
Any idea?
...
- 371
1
vote
1
answer
69
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Cisco 4500x configure fast-hello interface with multiple ports
I have a pair of cisco 4500x-32 and i configured VSS between then but i am using just 1x 10G interface for fast-hello packet and here is that interface configuration:
interface TenGigabitEthernet1/1/2
...
- 577
2
votes
2
answers
99
views
Cisco IOS - how can I make the guestshell be reachable via VRF?
I am currently trying to set up a cloud application on the guestshell of an ISR4331. It installs a connector that needs to have connectivity to the internet. I assume the issue is not specific to what ...
- 163
0
votes
1
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582
views
Configure NCS540 IOS XR router works as Layer 2 switch
I have an NCS 540 Router and would like to config it as an L2 Switch. In the diagram, PC2 and PC3 should get the IP addresses from pfSense(DHCP and DNS). How can I setup the trunk port for the NCS540 ...
- 1
0
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0
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28
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Cisco Firewall 5512 NAT cause IP randomly mapping to the host
I have an ASA 5512 firewall that has configured with 2 public IP addresses.
I use static nat to explosive https service and use PAT to allow my DMZ web server to access the Internet. The CLI are shown ...
- 1
0
votes
0
answers
52
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Is there a password policy configuration for setting up expiration date on cisco IOS?
Even I tried to find it from cisco homepage..
It seems it doesn't exist.
Is that only possible to set up on TACACS+ or RADIUS?
0
votes
1
answer
72
views
GNS3 Router Telnet Configuration
I configured the IP address and telnet for my Cisco router but on GNS3 it shows a different IP address. When I ping the router from my Ubuntu virtual machine using the IP address I configured the ping ...
- 1
0
votes
0
answers
156
views
Show on a Cisco 3850 Switch if a new IOS is installed
We have some Cisco 3850 that we never get downtime to do software upgrades (current uptime of switches is over 4 years). Tomorrow there is power works in the room so these switches will lose power so ...
- 383
1
vote
2
answers
232
views
What interfaces does a Cisco iOS Router allow SSH Console access on?
I am have trouble understanding how Cisco iOS maps console access services like SSH to IP addresses.
Assume the following:
There are no acls blocking traffic
There is the typical SSH server ...
- 135
0
votes
1
answer
271
views
Naming ASN something else than "default", Cisco IOS XR
I'm trying to configure a BGP and VRF (for a L3VPN) on a Cisco ASR9000 router, as per this tutorial.
I'm on the first section ("Configuring Multiprotocol BGP on the PE Routers and Route ...
- 1
0
votes
1
answer
191
views
How to change the AS number without losing the old BGP configuration?
I use Cisco with IOSv and would like to change AS number without losing the old BGP configuration.How to change the AS number without losing the old BGP configuration?
0
votes
1
answer
323
views
What could be blocking ARP?
I have a metro ethernet link between two offices with Cisco C3560X's on each end. Actually, I have two links. (We are switching from one provider to another.)
I can't get the new link to work. Pinging ...
- 464
0
votes
0
answers
93
views
Admin IOU L3 switch
Problem with IOU l2 switch
By Konstantinos Dimos
July 31, 2022 at 3:12 UTC
Hi, under Ubuntu 22.04 LTS, gns3 and local server I am trying to manage switch IOU L3 switch, although at the begining I was ...
1
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1
answer
321
views
how to limit or block broadcast traffic on ASR920 service instance EVC
I don't want to turn off all port,
I want to block completly broadcast traffic,
or the best to limit rate to 500 pps broadcast, all more to drop.
Is there any way to do it on Cisco ASR920?
I have ...
- 31
2
votes
0
answers
342
views
Cisco Access Switches: Monitoring AAA server dead via SNMP?
This is a new setup of Cisco access switches (2960S, 2960X IOS with 15.2(2)E9, but mostly C1000 with IOS 15.2(7)E*), with a Cisco ISE 3.0 as authentication server for 802.1X, config style is to be ...
- 8,826
0
votes
1
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151
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BGP Protocol configuration between two VPC
I would need to configure a cross connect between two VPC networks via SFP Fiber. Unfortunately I'm new on BGP configuration and would need confirmation that I'm doing it on the right way...
I have ...
- 103
0
votes
1
answer
2k
views
Cisco ASR 1001 transceivers not working
I've a Cisco ASR 1001 v03.
When it got to my hands it wouldn't save the config after reboots, after some research I found out the config-register had a wrong value and it was fixed by running ...
- 123
3
votes
1
answer
323
views
Cisco 9400-Supervisor Engine 1XL uplink help
I have inherited a Cisco 9400 with 6 line cards installed. I am trying to use some ports on one of the cards. I noticed that there is no link activity lights, no indication of any activity.
I think ...
- 85
1
vote
1
answer
105
views
Cisco 4500X TCAM question on PBR
I have a pair of 4500x in VSS mode and i have 100-150x SVIs and i have PBR under those SVIs and i am changing their next-hop, i want to know PBR and changing next-hop happens in TCAM, hardware or it ...
- 577
0
votes
1
answer
69
views
Cisco ACL Entries
I have a cisco 4500x and n5k-5672up and in their datasheet mentioned that we can have "Security ACL Entries (1K=1024) 128K (64K ingress and 64K in egress) Shared with QoS" for 4500x and &...
- 577
1
vote
0
answers
82
views
TACACS Through ASA L2L Tunnel
Hello see below network diagram.
I am trying to configure the Branch Router (10.1.1.1) to use TACACS AAA on the HQ-AAA-Server host (192.168.10.10). TACACS works fine for the Branch-FW1 ASA device ...
- 171
2
votes
0
answers
238
views
Problem with BGP aggregate-address behavior in IOS when a large number of OSPF routes update all at once
We have a Direct Connect setup to AWS using BGP. We are running a ISR4451 with IOS XE 16.03.06.
I have a strange situation where the AWS BGP neighbor drops our connection with the notification: ...
- 123
2
votes
1
answer
267
views
AAA Authorization on IOS
Still working away on a project (not for real life deployment so don't worry about seeing passwords).
I have a Tacacs server set up for centralised AAA. I am trying to set up two users, "admin&...
- 171
1
vote
2
answers
412
views
events log in cisco
Is there log file just like events file in windows showing what happened,who did what, kind of ? I could not see with show archive log.some switch goes down and support guys plug off/on cisco switch, ...
- 145
1
vote
0
answers
384
views
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 ...
- 1,700
4
votes
3
answers
291
views
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 ...
- 61
0
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0
answers
79
views
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 ...
0
votes
0
answers
139
views
How do I load VLAN database between switches (CISCO 2960)?
I glad for any help on this topic
--
netanel
0
votes
2
answers
68
views
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
0
votes
0
answers
767
views
No Voice commands on cisco router
I cannot find voice commands on my router,
I have licenced it but no voice commands or sip are found
Its on packet tracer.
Cisco router 2911
Thank you
- 1
0
votes
1
answer
694
views
Addresses in router's subinterfaces overlapping [duplicate]
I can't really understand why I'm getting overlapping addresses in subnets when they're between the allowed range.
I have the network 192.168.1.0/24, and I have to create 3 subnets:
A - 58 Hosts
B - ...
- 135
0
votes
1
answer
67
views
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?
- 103
1
vote
1
answer
229
views
ARP sending an ARP request on changing port IP address
Using the c7200 images on GNS3. I configured two routers as so:
With arp debugging on, after assigning an ip address I see that each router sends a gratuitous ARP response packet (only debug output ...
- 35
0
votes
0
answers
160
views
Cisco DHCP using dynamic updates
I would like to use a configuration on a Cisco router that allows for clients to resolve the names of other clients without the use of mDNS. I have following configuration:
roTST01#show running-config ...
- 1,700
0
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0
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567
views
Can ping from VPC 1 to router and VPC2, but can't ping from switch to VPC2 or router
I have a simple, linear topology in GNS3 that goes like this.
VPC1 > Switch > Router > VPC2
I have the default static IP Routes on the router set to 0.0.0.0 0.0.0.0 Ethernet0/1 and Ethernet1/...
- 135
0
votes
1
answer
154
views
How to stop automatic entry as privileged exec from console login?
I am configuring my Cisco router and trying to set up access levels.
I was under the impression that level 0 was a very limited mode which almost only allows users to enter the enable command to enter ...
- 135
2
votes
2
answers
309
views
Unable to add an abbreviated IPv6 to a Cisco router
I am very new to networking and playing around with GNS3. I am trying to configure a router to have 2 IPv6 addresses in a single interface (as far as I understood, this is possible with IPv6)
I ...
- 135
0
votes
1
answer
96
views
IP Source Guard On Static Networks
I am running a set of Cisco C9300s. I have them configured with ip dhcp snooping, and ip arp inspection with ip dhcp snooping trust and ip arp inspection trust set on the fiber link between the 2 ...
- 461
0
votes
1
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203
views
In France , what language is the Cisco IOS for routers and switches?
If I accept a Network Engineer job in France, what language will the Cisco , Juniper, etc, IOS communicate in?
If it is in French, is there an acceptable workaround that I can install in routers that ...
- 3
0
votes
1
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171
views
Why does a Cisco router advertise a prefix with NDP RA when it has an address in that range?
If I write
interface Vlan1
... {ipv4 config} ...
ipv6 address 2001:DB8:5432:101::/64 eui-64
ipv6 address FDAA:DB8:5432:101::/64 eui-64
ipv6 enable
ipv6 nd prefix 2001:DB8:5432:101::/64
ipv6 nd ...
- 103
0
votes
2
answers
294
views
Steps for upgrading to Cisco DNA Center?
Has Anyone upgraded from cisco Prime to Cisco DNAC, if so then Does anyone have Steps (Prep Work) checklist suggestions before beginning the Brownfield Deployment of Cisco DNAC ?
3
votes
1
answer
270
views
Cisco ACL numbering
This is a small technical question. I can't seem to find any information on this, so I thought I'd ask here.
I'm currently studying for my CCNA and I'm currently on the topic of ACLs. On IOS standard ...
- 133
0
votes
1
answer
791
views
4500x ios upgrade
I have a Cisco 4500x-32SFP (with Enterprise License) with cat4500e-universalk9.SPA.03.04.04.SG.151-2.SG4.bin ios and i want to upgrade it to cat4500e-universal.SPA.03.11.03a.E.152-7.E3a.bin which is ...
- 577
0
votes
1
answer
467
views
Cisco ip helper-address
I am looking at the DHCP documentation and i cannot seam to find how to configure the router to use a loopback interface as the relay-agent. My objective is to use option 82 so that the dhcp server is ...
- 327