Questions tagged [cisco-ios]

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

Filter by
Sorted by
Tagged with
5
votes
1answer
573 views

Time Cisco Router reload not always mentioned

Im trying to measure our cisco router availability data based on downtime happened. I assume from show version, the time mentioned in tag "System returned to ROM" is when reload started, and next line ...
4
votes
3answers
26k views

Meaning of the ip default-gateway L2 switch

What is meaning of the ip default-gateway command on a Cisco L2 switch? I read something about it on the Internet, but there was written that it allows you to Telnet to the switch. I am little bit ...
4
votes
1answer
4k views

load-balancing on congestion, OSPF over MPLS

I have a network of routers with two clients at both ends, as shown in the Figure below. All the routers use OSPF routing protocol over IP, and the three routers inside the "MPLS backbone" subnetwork ...
4
votes
1answer
990 views

QoS between two sites

I have a following topology where Internet service providers for both sites provide 10Mbps connection: There is a GRE tunnel between the sites and I would like to ensure that this tunnel is up even ...
4
votes
1answer
160 views

Cisco IOS: OSPFv3 route cost

Cisco IOS 12.4T and later: show ip ospf rib informs about the cost for each network learned by OSPFv2. What command does the equivalent for OSPFv3?
4
votes
1answer
735 views

Interpreting Cisco logging symbols

When I issue a "show logging" command to see the locally buffered logs, the log statements are displayed sometimes with an asterisk in front of the date and sometimes with a period in front ...
4
votes
1answer
369 views

Cisco APIC command equivalent to Cisco IOS `show terminal | include Length`

Whenever I run show running-config leaf/spine from APIC, I notice that there is a pause which is --More-- at the end of the first page. What I'm trying to achieve is to disable that so that I can ...
4
votes
2answers
505 views

After I set the “router rip” networks, how can I check it?

In my CGR1240 I have set network 192.168.1.0 to my router rip, but how can I check it? If I add more networks in rip, how can I list all the networks I have added? I can not show the router rip in ...
4
votes
1answer
616 views

Config logging on which cisco IOS?

I want to configure configuration logging on network devices by running following commands. archive log config logging enable I want to know which Cisco IOS and device support it? I used cisco ...
4
votes
1answer
3k views

Disable reset button on Cisco 2950?

On the front panel of a Cisco 2950 is a button which can be used to reset the switch to factory defaults, when held down for a few seconds. Does anyone know of a way to disable this within IOS? Many ...
4
votes
2answers
15k views

Can't ping other vlan on same stack switch

I have to setup a stack of 3 Cisco 3850 switchs. They are licences to IP Base feature. I inspirated my setup from an another configuration we got here but those switches have the IP Services IOS. ...
4
votes
3answers
2k views

DHCP Server Port-Based Address Allocation on Cisco switch 2960-x

I am trying to configure DHCP Server on a Cisco 2960-X switch to achieve port-based address allocation. I would like the IP address assigned to any device connected to that port to be the same every ...
4
votes
1answer
231 views

What is the minimum interval for IOS kron?

Am I correct that minimum interval for IOS kron for reoccurring tasks is 1 minute(kron occurrence test in 1 recurring)?
4
votes
1answer
503 views

Cisco Router as Terminal Server Buffering Issue

I have configured a Cisco 2911 with an HWIC-1T card as a terminal server using the configuration below. I can telnet to port 2003 of the loopback address and establish a serial connection to a laptop ...
4
votes
1answer
220 views

PAT not translating at all

I am studying for my CCENT. I threw together a PAT practice lab. Other than DHCP and RIP everything is pretty stock. No VLANs No security Just NAT overload on ACCESS router. I am stumped why it isn'...
4
votes
2answers
749 views

Why the Cisco Router's loopback interface can not be showed up by default?

By default, why the Cisco Router's loopback interface can not be showed up? Router#show ip interface brief Interface IP-Address OK? Method Status Protocol ...
4
votes
1answer
515 views

Filtering IP packets that contain IP options using ACL

Is it smart to have ACE #deny ip any any option any-options enabled as part of hardening the router? Is there some legitimate traffic that use IP options? Or should I use selective drop?
4
votes
1answer
4k views

Create a internal connection between ISR 4451 and EtherSwitch submodule

In a Cisco ISR 4451 we install a EtherSwitch 48 Port Module. The ISR is working and the EtherSwitch Module too. Now I want to create a route from ISR to EtherSwitch and read some Manuals and Forum ...
4
votes
2answers
2k views

IOS NAT: Inside static NAT mapping one internal IP to multiple external ones

Will the following work? ip nat inside source static 1.1.1.1 2.2.2.2 route-map x ip nat inside source static 1.1.1.1 2.2.2.3 route-map x (say the remote net is 20.20.20.0 in both cases) What I'm ...
4
votes
1answer
19k views

% Authorization failed. message appear when I try to connect to the switch using local DB user name

I configured aaa using Tacacs+ on a switch and a router but when I try to connect to the switch through SSH it just accept Tacacs+ users when I try to use local DB user I got "% Authorization ...
4
votes
2answers
2k views

Cisco - MtR alternatives

I trying to establish if there is a function within IOS somewhere that can provide the same results of MTR , i know it can be run from Juniper devices / *Nix & Windows devices. Goal is to ...
4
votes
1answer
1k views

Working with Cisco IOS.sh and grep

I just learned about Cisco IOS.sh and found that you're able to run commands similar to UNIX based systems on Cisco devices. First question: Is IOS.sh router or switch specific? Or are they able to ...
4
votes
1answer
134 views

CISCO IOS's feature Secure Shell Version 2 Enhancements for RSA Keys

I have a switch C3750V2-48PS with IOS ver. 12.2(55)SE5. I wanted to copy to it public key for the ssh client but I do not have following command available Switch#configure terminal Switch(config)#ip ...
4
votes
2answers
175 views

Automation out of the box?

Can anyone point me in the right direction ? I have been recently learning python with the goal of learning more about network automation, I can copy, paste, tweak and adjust a simple script to ...
4
votes
2answers
489 views

NTP architecture questions

I have a question about NTP. We want to setup our core switches as NTP master for our network. We have three data centers. Site A : Two Nexus as core Site B : two Nexus as core Site C : two 6800 (in ...
4
votes
1answer
1k views

How to use secondary internet exclusively for one host?

I currently have two internet connections coming into my main office. The primary connection is regular static IP cable service and the secondary is a dedicated MPLS Ethernet connection. The primary ...
4
votes
1answer
1k views

Configuring a Cisco router behind a fiber cable modem

I'm trying to configure a Cisco 886VA router to use a full-duplex fiber cable modem for internet access. The modem (Alcatel-Lucent) is pre-programmed and doesn't support DHCP (192.168.1.0/24, gateway ...
4
votes
1answer
302 views

IOS 15 Port Forwarding

We need a router to translate a TCP port for a connection between an inside device and an outside server. The outside server (1.1.1.2) will establish a connection to the inside device (10.0.0.10) on ...
4
votes
2answers
22k views

SNMP: Configuring/Enabling SNMPv3 on Cisco IOS and SNMP Agent

I have been configuring and using SNMP v2c on Cisco routers. Due to the obvious advantages in SNMP v3, I am planning on enabling SNMP v3 on SNMP v3 supported devices. Could someone let me know: The ...
4
votes
1answer
688 views

Cat6K parity failure and long SSO failover

From a Cat6K, RP crashinfo indicates parity error. Guidance seems to be to not do anything unless this happens more than once in 12-month period. At what point do you push Cisco for hardware or RAM ...
4
votes
1answer
339 views

Switch updating - Cisco Prime

I'm tasked with mass updating of our Cisco switches via Cisco Prime. Is it possible for the update to fail? Can the switch 'hang' in reboot loop? What if I tell Cisco prime to backup running image? ...
4
votes
2answers
736 views

Cisco Router GigabitEthernet interface can not add ip address?

Cisco Router GigabitEthernet interface can not add ip address? Router(config)#interface gigabitEthernet 2/1 Router(config-if)#ip add ? % Unrecognized command Router(config-if)#ip add 12.12.12.1 255....
4
votes
1answer
2k views

“debug” to show vlan of incoming frames

At a remote site where I can't easily set up SPAN and do a regular packet capture, I need to see the VLAN of incoming frames on a trunk interface. Is there a debug command for a Cisco Catalyst 3560X ...
4
votes
1answer
858 views

IOS to ASA dynamic and static VPNs - sharing same crypto ACL?

Is it possible to have a dynamic and static VPN between the same IOS router and ASA, sharing same interesting traffic/crypto ACL on the ASA end? The two devices in question: ASA 9.1 - hub/termination ...
4
votes
1answer
192 views

Default authentication/authorization/accounting list on all lines?

Am I correct that if one has not specified a named authentication list(login authentication ... under line configuration), authorization list(authorization .. under line configuration) or accounting ...
4
votes
1answer
2k views

Cisco ASA RRI and OSPF redistribution

This is a follow-up question based on this original question. The following topology is present: The Cisco ASA is our Internet firewall, as well as VPN gateway, terminating VPN connections. The ASA ...
4
votes
1answer
555 views

How to configure IOS/IOS-XE routers to prompt for users after “enable”?

I need to get to a point where my routers ask me for a user and password after I've entered the "enable" command. like this: Can anyone help with this? Thanks!
4
votes
1answer
664 views

Cisco IOS | Can I use same transform set in different crypto maps?

On a Cisco IOS router can I use the same transform set with multiple crypto maps? I.E. Is the below configuration example valid? ! crypto isakmp policy 1 encr aes 256 authentication pre-share ...
4
votes
1answer
2k views

IOS-XE: request system shell vulnerability

Catalyst-3650#request system shell Activity within this shell can jeopardize the functioning of the system. Are you sure you want to continue? [y/n] y Challenge: 94d5c01766c7a0a29c8c59fec3ab992[..] ...
4
votes
1answer
248 views

Could MD5 digest be synchronized between VTP Server and Client if there is a discrepancy in Switch Versions?

The MD5 digest between the VTP Server located on Switch1 and the VTP Client located on Switch2 have been synchronized. Although the steps from this Q&A have been followed, a trunk has been ...
4
votes
1answer
155 views

Cisco 2921 SEC upgradable to WAAS?

Does anyone know if it is possible to upgrade a Cisco2921-SEC/K9 to Cisco2921-AX/K9 (WAAS)? I mean is it the same hardware and all I need is to upgrade the licence? /Andreas
4
votes
1answer
1k views

Cisco IOS outbound filtering

I am hoping someone can help with configuring a Cisco 881 which does NAT for the vlan and has a handful of port forwards from the WAN interface to hosts on the vlan. I've created an extended access-...
4
votes
1answer
9k views

Line protocol is down on Cisco Router / IOS 12.2

I have this error on a Cisco router running IOS version 12.2. This coincide with an error received on our alarming system saying that on this router we have an interface with "line protocol down". ...
4
votes
2answers
3k views

View Power On Self Test (POST) details on Cisco 1841 Routers and Cisco 2950 switches

I need to view POST details on Cisco 1841 Routers and Cisco 2950 switches. I have tried show post and show diagnostics post. However, both these commands are not available. What is the command that ...
4
votes
1answer
1k views

limit bandwidth on a Cisco switch port,

Our company has a 3/.5 DSL connection. On this connection we have a VPN where the execs are able to access files on the network as well as VOIP. On this connection we also have our exchange email ...
4
votes
0answers
106 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
2answers
82 views

Routing Table Eligibility

I have an architecture which is that each remote site has 2 Dialer interfaces dialling into a virtual-template core which authenticates the sessions and applies attributes from a RADIUS server. OSPF ...
4
votes
0answers
238 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 ...
4
votes
1answer
1k views

Enable SNMP traps for ACLs using Cisco IOS?

Does anyone know if it's possible to enable SNMP traps to be sent from a Cisco IOS device when an ACL blocks traffic? I'd like to send a trap whenever a deny statement gets a hit. I've only been ...
3
votes
3answers
686 views

HTML folder located within IOS Image file?

I have two 3750G switches in a Cisco switchstack I wasn't sure if this was common at one point or not, but when I go to copy a new IOS image .bin onto flash, It is showing not enough space. Upon ...

1 2
3
4 5
11