The operating system used on the majority of Cisco's routers and switches; a package of routing, switching, internetworking and telecommunications functions tightly integrated with a multitasking operating system. For Apple's mobile device OS, use apple-ios.

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3
votes
1answer
3k views

Output Drops on Cisco Switch — Counter?

I was always under the impression that the Total output drops was a counter that goes up until it resets (or maybe wraps around 4 billion). However, this seems to indicate otherwise, or something is ...
4
votes
1answer
529 views

Can somebody please explain IOS line authentication?

I'm trying to understand a config on one of our Cisco routers (teaching myself iOS) and have run into a problem with one line. Can somebody please explain the "line enable" piece of the command below ...
7
votes
3answers
9k views

How to obtain Cisco IOS firmware?

Quick and simple question, but I've not been able to find an answer around. I have a Cisco ADSL router (model 877). I don't have any Cisco support contract. How can I obtain an updated firmware for ...
1
vote
3answers
97 views

Cisco ACL Not Applying

This is probably something extreamly simple but I am executing the following code to block usage of port 80 on ip 192.168.1.50 and it does not seem to be working. The interface is right and I am using ...
0
votes
2answers
86 views

Cisco XR Interfaces

I'm trying to figure out if a device which is running Cisco IOS XR is affected. The advisory is published here Assuming I have the vulnerable OS versions, Now I want to check if I have a Cisco Line ...
2
votes
1answer
9k views

How to disable ICMP redirect packets in Cisco IOS?

I'm studying a "good practices" document for Cisco IOS, and one of its controls tells me to disable ICMP Redirect packets in the router. Sounds reasonable. So I go test it in Cisco Packet Tracker (a ...
4
votes
1answer
84 views

Cisco IOS XR version clarification

I've run across this cisco advisory It says: This bug was introduced in Cisco IOS XR Software release 3.6.2 and is fixed with SMU hfr-k9sec-3.6.2.CSCtd74795. The SMU ID for this fix in ...
4
votes
1answer
314 views

cisco 870 assign IP

I'll try to be "short." I've successfully enabled http server option on my Cisco 870, now I need to reach it and use the web based configuration. I haven't found how to assign an IP to the router ...
2
votes
4answers
2k views

Cisco 1800 series router simulation program

I need to know how to program these routers for school, but I need to exercise at home. Are there simulators for the console interface, for learning purposes? I took a look at eBay to get one, but ...
0
votes
1answer
99 views

Will cisco 3750-e switches run the old ipservices ios code?

was wondering about cisco 3750-e switches. Will they run the old ipservices ios code? Or do they only run the univeral image? Thanks
2
votes
2answers
3k views

Cisco Terminology: flash and nvram

I'm a student that will be taking my CCNA exam in early June and I'm doing a lot of practical revision, I tend to get sidetracked by little things such as this question I'm about to post. It's ...
9
votes
1answer
383 views

Simple Multicast Design

In order to support desktop imaging requirements I need to correct the multicast design on an existing network, but am not well versed in this subject. The diagram below gives a basic example of the ...
0
votes
1answer
75 views

ios: how to stop output of a show command

Can anyone tell me how to break output of a show command in cisco ios? Say I don't want to see all of 'show run' and I got the info I need, what keys can I press to stop it from printing the rest of ...
0
votes
3answers
1k views

Configure hairpinning on Cisco 871 IOS 12.4(15)T4?

I'm a newbie to IOS. In the past I've used consumer routers which seem to have the smarts to automatically route requests to internal hosts addressed by their public name back to the internal network. ...
0
votes
1answer
737 views

Cannot login to Cisco 2911 over ssh?

30 minutes ago my router is not accepting ssh connection. Well, ports is open (due to nmap), ssh simply hangs on reading from Cisco socket (observation from strace): /home/rafal/.ssh/id_dsa-cert type ...
3
votes
2answers
2k views

Is there a Cisco IOS command that will show DIMM info per slot?

I have a Cisco 2811 with 256MB DRAM. I know this because show version tells me so. I want to upgrade it to 768MB. I know that this takes 1 - 512MB amd 1 - 256MB DIMM. I know that the 2811 has 2 ...
0
votes
1answer
2k views

Can't enable IPv6 in Cisco 2800 router running IOS 12.4T

I can't enable IPV6 in a Cisco 2800 router that runs iOS version 12.4T. I followed the summary steps section in Cisco's web page . But whenever I type "ipv6" on the command line (as in 'ipv6 ...
2
votes
2answers
2k views

Cisco 2610XM: Advanced Enterprise vs Advanced IP Services?

What are the differences from the Adv. Enterprise firmware and the Adv. IP Services? From the 2610XM perspective. Regards,
0
votes
1answer
165 views

More than 8 classes in a policy-map - Cisco 3560

It appears I am limited to 8 classes per policy-map. Here is the error message when using the Cisco Network Assistant: The policy "policy-name" contains more than 8 policers, which means it ...
0
votes
3answers
567 views

List Of Cisco IOS Devices

I want to start playing a bit with Cisco IOS and I have a Cisco WAP200 Wireless Router here, so I want to know if it comes with IOS and also where I can find a list of the IOS devices so I can know ...
2
votes
2answers
196 views

DMZ-to-outside Access Lists

I'm learning about firewalls and access-lists, and I'm trying to decide what sort of access list I should have on the DMZ, particularly regarding outbound traffic. There's certain outbound traffic ...
1
vote
1answer
1k views

Cisco IOS: Is ip inspect used?

There is a Cisco IOS router with the following code in it. The below code seems to define Context-based Access Control Engine inspection rules. I don't think any of this is used. The only occurences ...
3
votes
5answers
5k views

Is there a way to submit a batch of commands to a Cisco router and have them execute from the router?

I need to change the configuration of a remote (6 hours' drive) client's Cisco 871 (IOS 12.4.15T) from my location because of some new internet service at his location. To be more precise, I need to ...
6
votes
1answer
6k views

Why would Windows Server not respond to DHCP DISCOVER?

My network was working just fine and I broke it. There is a Cisco 1711 router which was configured to hand out DHCP leases to the client PCs. I have a domain controller (Server 2008) on the same ...
2
votes
2answers
5k views

Restoring a Cisco router config using a config file

I'm working with a Cisco router over telnet (actually PuTTY), and I'm a newbie to ios. I'm slowly getting the hang of it, but have a very basic question: I have issued a show running-config command ...
1
vote
1answer
129 views

IOS traffic-export equivalent for Junos

In IOS the traffic-export command allows you to take incoming packets and send them, unaltered, to a specific interface. Is there an equivalent way to do this in Junos? I've got a J-series 2350 here. ...
0
votes
1answer
100 views

Cisco T1 Routing Help

Thanks to someone on this site I was able to get the Serial0/0 interface up. I now have: DCD=up DSR=up DTR=up RTS=up CTS=up My next challenge seems to be in the routing and/or PC ip setup. ...
1
vote
1answer
254 views

Cisco 1760 T1 Setup

My 1760 has a WIC1-T1 card in Slot 0 and the slot 0 "OK" light is lit. When the router boots it shows that it sees the T1 card. I would like to configure my T1. I received the following details from ...
0
votes
1answer
651 views

Cisco 2911 - problem with DHCP

i am configuring DHCP daemon on Cisco 2911. At some point i assigned address 192.168.50.50 to one box (using MAC address 'relation'). When I wanted to saved config - I got warning, that address ...
0
votes
4answers
2k views

How to start Cisco 2911 with presaved configuration?

I briefly configured branch router Cisco 2911 and saved config. Unfortunately - after rerun Cisco needs "copy startup-config running-config" to read configuration (I really need this - for example to ...
1
vote
1answer
95 views

IOS not saving evaluate rule in access-list

I have a basic firewall set up on an pretty od IOS in form of IPv6 access list exterior-in6 evaluate exterior-reflect sequence 1 permit ipv6 any host [my external address] sequence 10 permit ...
0
votes
1answer
453 views

Cisco 851 (IOS) router: FastEthernet 4 (WAN) got the shutdown flag

At a customer location there was a Cisco 851 router (which uses IOS). The PCs on location were all of a sudden unable to connect. We came on site and found that FastEthernet 4 (the WAN port) was ...
0
votes
2answers
2k views

Cisco IOS BVI ACL: Only allow established UDP

Related: Cisco IOS ACL: Don't permit incoming connections just because they are from port 80 I know we can use the established keyword for TCP.. but what can we do for UDP (short of replacing a ...
0
votes
1answer
564 views

BVI vs Bridge routers

What is the difference between BVI and Bridge on Cisco IOS routers?
1
vote
2answers
318 views

Cisco IOS ACL types

The built in command help list displays access list types based on which range. router1(config)#access-list ? <1-99> IP standard access list <100-199> IP ...
0
votes
3answers
5k views

Cisco IOS: access-list logging rate-limited or missed packets

How do we fix these errors? 2629753: Dec 29 09:03:56.521 EST: %SEC-6-IPACCESSLOGRL: access-list logging rate-limited or missed 2 packets This is a Cisco 871 router with BVI and access lists.
0
votes
1answer
332 views

Cisco IOS ACL: Don't permit incoming connections just because they are from port 80

I am going much based on my memory and I may not be correct on all of this. On a Cisco 851 (IOS) that uses a BVI or a bridge-route (the servers on the inside are configured with static and public IP ...
0
votes
3answers
6k views

Why do Cisco IOS routers hang in the middle of large downloads?

After a few years in use. We have seen Cisco 871 and 851 routers that would hang if you had a single download that was more than 100M large. It is intermittent. Sometimes the problem goes away, ...
1
vote
0answers
879 views

Max STP instances reached on Cisco 2950 despite not actively using 64

I have a Cisco 5505 switch running CatOS connected to a number of Cisco 2950 switches running IOS. The 5505 switch supports a large number of vlans (I'm guessing 1005), yet the 2950s only support a ...
0
votes
1answer
108 views

Restrict NAT in IOS to only one public IP

I've managed to enable port-forwarding on my Cisco 877 but I wasn't able to find a way to specify a single accepted IP from the outside. Any link to a Cisco documentation or commands to type in IOS ...
0
votes
3answers
1k views

Can't connect to PPTP server outside of network

I'm trying to configure my Cisco 881 running IOS 15 to allow pptp connections to servers outside of the network. I know the PPTP server is configured correctly, because a)it's a clients VPN, and b) ...
0
votes
3answers
3k views

Issue forwarding port through Cisco 881 router

I am ultimately trying to set up a PPTP VPN server inside my firewall, but to verify that the router will be configured correctly first, I am trying to pass SSH through the Cisco 881 to the SSH server ...
0
votes
1answer
3k views

IOS NAT with multiple interfaces

I am trying to create a DMZ type environment between two internal networks using Cisco NAT. The below configuration is working to permit the two 'nat outside' interfaces to access the dmz 'nat ...
3
votes
1answer
2k views

Monitoring incoming/outgoing packets on a Cisco switch

I would like to monitor (i.e. have the switch print out packets) incoming and/or outgoing packets on a Cisco switchport. For instance, I'd like to be able to tell it: Print to the log all packets ...
0
votes
1answer
2k views

Cisco IOS: One SSID doesn't pull from the correct DHCP pool

I have 2 SSID setup in my Cisco 881W router. Our internal ssid pulls from the right DHCP pool (wpool), while our guest SSID does not pull from the right pool (gpool) Here is the router config ! ! ...
5
votes
2answers
811 views

Cisco IOS: Segregating VLANS

I am trying to segregate the traffic on the VLANs, as one is our visitor VLAN (VLAN 3 is the guest lan). It is a Cisco 881W router. Here is my VLAN configuration: interface Vlan2 ip address ...
2
votes
2answers
6k views

Example mrtg config to monitor Cisco CPU/memory usage

I have an existing basic MRTG setup done using cfgmaker to monitor the traffic of our Cisco router. I'd like to add configuration sections to mrtg to have it monitor the CPU usage (min/avg/max if ...
0
votes
1answer
47 views

Cisco 871w security

I purchased a 871W ISR for a small business and want to know what's best use practice when setting up security for this type of router. At the present time I have a static IP assigned to it and can ...
0
votes
2answers
117 views

Cisco command wont work on syxtax checker

I'm trying to validate the building of a tool for managing Cisco ACL commands. Thing is i'm using the aclcheck sintax validator (i dont own cisco equipament) with the following command do check ...
2
votes
2answers
4k views

Cisco IOS: NAT overload for two WAN interfaces

I have a feeling the answer is policy-routing, but I'd like someone to clarify that. Basically I'm not having any luck getting NAT to work with two WAN interfaces. I have two WAN interfaces: fe0/1 ...