Questions tagged [cisco-ios]

For discussion about Cisco's Internetwork Operating System - Cisco IOS

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How to break apart an IPv6 /56 6rd delegated prefix from ISP into multiple /64 VLANs for use with SLAAC EUI-64? [Cisco]

I have CenturyLink Internet service, and they have a 6RD IPv6 deployment where they hand out an IPv6 delegated prefix /56 block to me and allow me to use it as I wish. My Cisco ISR router receives the ...
4 votes
0 answers
157 views

Redundant physical interfaces for Cisco pseudowire-class

I have a link which is LT2P from a site router R1 (Cisco 867-VAE, IOS 15.3) which has two external interfaces defined (dialer1 and vlan-1000), but only one plugged in (first is ADSL, second is ...
4 votes
0 answers
300 views

IOS XE minimum frame size

I recently encountered an issue upgrading from an IOS device to an IOS XE ASR 1000 router concerning Ethernet Over SONET (EOS). VLAN tags are used to map traffic from the hub router to SONET ...
3 votes
0 answers
1k views

Dual ISP NAT Failover Not Working

I have a Cisco 1841 router with an HWIC-4ESW switchport module attached to it. Fa0/0 is connected to ISP1 and Fa0/1 to ISP2 and both are "ip nat outside", the switchports are in interface Vlan 1, ...
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2 votes
0 answers
153 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 ...
2 votes
0 answers
150 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: ...
2 votes
0 answers
3k views

Cisco AIR-AP1852i-E-K9 stuck in "waiting for uplink[...]" after startup

I pulled an old cisco AP from a shelf today at work to test something, and after starting up and connecting with PUTTy, i was greeted with (after startup), this - repeating over and over: [*02/16/...
2 votes
0 answers
256 views

Cisco ISR Zone Based Firewall dual stack not matching returning traffic for ipv6

I have a bit of a problem with my Cisco 1921 ISR config. I have ipv4 (obviously) and also native ipv6 connectivity in my home lab. I am trying to set up the zone based firewall. With ipv4 traffic, the ...
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2 votes
0 answers
1k views

NVI based NAT on Cisco ISR terrible performance

I am trying to experiment with a Cisco ISR 1841 and have configured NAT on the device. The intention is to simulate it being a broadband router. I understand that this is not the best performing ...
  • 181
2 votes
1 answer
113 views

Routing failed after define static route on core switch

Current connection path: 10.40.20.0/24 desktop <-> access switch <-> core switch <-> 10.30.15.33 NAT firewall for internet access Objective: adding additional path as following to ...
1 vote
0 answers
64 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 ...
  • 161
1 vote
0 answers
211 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 ...
  • 1,670
1 vote
0 answers
69 views

Upstream QoS garanteed bandwidth

In the network I'm trying to manage there is a satellite link, the upstream of which is ~ 7 Mbps. In this upstream, I need to allocate 1.5 Mbps of guaranteed bandwidth for one single host, but nothing ...
  • 45
1 vote
0 answers
247 views

Configue IOS DHCP server to respond to Option 60 class

I have a number of small networks each with about half-a-dozen mostly-fixed hosts. The routers on each network provide DHCP service for the occasional visiting engineer's laptop. I am adding IP ...
1 vote
0 answers
317 views

Amazon AWS VPN Bidirectional Device Access

After setting up an Amazon VPN connection and configuring my gateway using the downloaded configuration, I am able to directly ssh to the private IP of an EC2 instance in my VPC. However, both the EC2 ...
  • 11
1 vote
0 answers
1k views

ASR1006 IOS upgrade with ISSU

We were running Cisco ASR 1006 on single RP2/ESP since long time but today two purchased secondary (standby) RP2/ESP for redendency. Now question is how do i upgrade IOS on secondary RP2? I am ...
  • 4,301
1 vote
0 answers
674 views

Packets are disappearing

I have a server HP DL180 G6, connected to a Cisco switch (4948E or 2960). The server have 2 ethernet ports and ILO shared with data port #1. ILO setted up to request ip from DHCP. 1) When I connect a ...
  • 36
1 vote
0 answers
596 views

VPN tunnel with duplicate subnets

I have been tasked to setup a VPN tunnel with an external party's network, but I hit a bit of snag. I am currently running a Cisco ASA 5510 with private subnets of 10.1.2.0/24 on the "inside" network....
1 vote
0 answers
290 views

Able to test AAA to Radius Server from router but unable to log into Router with A.D

I am having issue with setting up my Radius server to authenticate before going to the router. I am able to do a test from the router successfully but once I exit the router and log in with my Windows ...
  • 51
0 votes
0 answers
26 views

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
37 views

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
0 answers
24 views

Is it possible to set maximum 32 PAT translations per global ip address?

So basically I'm trying to configure a cisco router (c7200) to use PAT with a pool of global addresses, and each global address should only support a maximum of 32 private addresses. I've been ...
0 votes
0 answers
73 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 ...
0 votes
0 answers
61 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 ...
0 votes
0 answers
57 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
100 views

How do I load VLAN database between switches (CISCO 2960)?

I glad for any help on this topic -- netanel
0 votes
0 answers
465 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
0 answers
94 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 ...
  • 1,670
0 votes
0 answers
414 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
0 answers
55 views

Is it possible to specify a bandwidth parameter per service instance?

I have a physical interface with multiple service instances and policer per service instance: interface GigabitEthernet0/3  switchport trunk allowed vlan none  switchport mode trunk  mtu 9192  ...
  • 1,325
0 votes
0 answers
34 views

Rate limiting xFTP traffic originating from a Cisco IOS router

We have some routers on marginal cell links that we need to pull files from using TFTP or FTP. During file transfers connections to the router become so slow as to be unusable. Is there a way to rate-...
0 votes
0 answers
901 views

Cisco erase nvram or erase startup-config doesn't work

According to this article, I can delete the current startup configuration files and return the router to its factory default settings with the erase nvram: and reload command. https://www.oreilly.com/...
  • 311
0 votes
1 answer
212 views

Issue w/ Cisco router and failed NAT and static default route

I have a cisco router that is using a VRF to support a site to site VPN tunnel. I have added a second network to the router for non-VPN standard internet use. My problem is that my default static ...
0 votes
0 answers
136 views

Cisco C3750 and PRTG netfllow

I have a core switch (backbone) of our network that broadcasts all the vlans to other switches. I am trying to configure netflow on the switch and link it up to a Netflow sensor on PRTG. I followed ...
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0 votes
0 answers
125 views

Cisco Guestshell - Bridging of VirtualPortGroup0

i'm fiddling around with ne virtual-services functions of IOS-XE. Is there a possibility to bring interface "VirtualPortGroup0" into a bridge domain with some physical interface of the router? It's ...
0 votes
0 answers
73 views

cisco zone-based policy firewall

How to limit the number of established connections for each host, that connect to the service? In the policy settings, I found only blocking by the number of half open connections. parameter-map type ...
0 votes
0 answers
427 views

Prioritizing SSH, Telnet, TACACS in Cisco IOS

For Prioritizing SSH, Telnet, TACACS locally generated traffic on Cisco ASR running IOS XR, we have: ssh server dscp 48 tacacs-server ipv4 dscp 48 Need the same for cisco GSR: 12416/PRP running IOS. ...
  • 51
0 votes
0 answers
165 views

I'm unable to see packet drops after configuration of QoS policy

I aim to send iperf traffic from Endpoint1(Client) to Endpoint2 (Server) with the following SR path = {R1, R2, R3, R4, R3, R2, R1, R2, and R3}. First of all, the traffic generated by iperf from ...
0 votes
0 answers
318 views

Cisco 1841 stuck on boot?

I found an old Cisco 1841 router and decided to boot it up to play with it a little. Everything seemed to be going ok but I guess something interrupted the boot. Last line is %SYS-6-...
0 votes
0 answers
56 views

What spanning tree IEEE protocol does the Cisco 1252AG Aironet access point support?

Link to data sheet We're running Cisco IOS version 15.2(2)JA1. What version of the IEEE STP is supported on the Cisco Aironet 1252AG access points? We are using the "bridge X protocol ieee" command. ...
0 votes
0 answers
499 views

Query on Cisco IPsec Licensing, HSEC-K9

I'm currently debugging an issue with IPsec tunnels and it seems like one of our client's NW engineers didn't install the HSEC-K9 license. The issue is that the new IPsec tunnels are not coming up ...
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