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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10
votes
2answers
601 views

How to safely install a new IOS image on a Cisco device when the installed flash memory size isn't enough for two of them?

Today I was updating IOS on a Cisco 877 router, and a problem came up: the installed flash memory wasn't enough to hold both the old and the new IOS images, so the new one couldn't be uploaded unless ...
9
votes
3answers
4k views

Why is my router CPU at 40% when no processes use more than 2%?

I have a problem, I have a Cisco 1841 running Cisco IOS 15, and I get strange behavior. The CPU usage is shown as 40%, but there is no processes that is using this much CPU power. Here is an ...
9
votes
1answer
382 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 ...
8
votes
4answers
197 views

Prevent end-users from purchasing apps on iOS

We are looking to deploy iPads from inside our organization. We want to be able to install apps for users, which can be done via Mobile Device Management. However, we do not want users to be able to ...
7
votes
3answers
8k 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 ...
7
votes
2answers
1k views

Can the iPad remember the iTunes password when using Meraki MDM?

I'm currently using Cisco Meraki MDM to manage apps that get pushed out to company-owned iPads. In order for the company to retain ownership of the apps we purchase, apps are installed through the ...
6
votes
4answers
1k views

Cisco IOS QoS prioritize SSH but not SCP

How can I prioritize ssh traffic to ensure low-latency but throttle SCP file transfers? I'm looking for a solution that is not host specific so I don't have to add lists of IP addresses. Thanks!
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 ...
5
votes
1answer
510 views

Tag/Untag VLANs from Port Perspective on HP Switch

I'm familiar with vlans and tagging, and we usually use the command line interface for our HP Layer 3 switches. I've done quite a few: vlan 10 untagged 21 I've always wondered if this was possible ...
5
votes
2answers
783 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 ...
5
votes
1answer
509 views

Setting spanning tree link “priorities” in Cisco switches

I've got a pair of C2960G-48 switches (running IOS 12.2(46)SE, if it makes a difference) with redundant trunks in place. On these switches there are a bunch of VLANs that carry quite heavy traffic at ...
5
votes
2answers
90 views

How can I automate the deployment of cisco IOS upgrades?

I was googling this and didn't turn up anything. If you have 100 some odd Cisco routers and switches how do you push out new IOS releases? Certain not by manually logging into every device. The only ...
5
votes
1answer
2k views

How do you NAT Hairpin in IOS 8.3+

As I asked here and duplicated here it appears NAT Hairpinning is the answer I'm looking for to allow internal servers to loopback through the ASA to access external IP's (without using DNS ...
4
votes
1answer
565 views

Why did my Cisco router hang?

We have a Cisco 1841 in our storage IDF that was originally running a 12.4(1) IP-BASE image; I wanted to upgrade to an advancedservicesk9-mz image, but the flash did not have enough space, so I ...
4
votes
1answer
116 views

Does Cisco IOS support the use of variables in its configuration?

I'm configuring a Cisco IOS (version 15) router, and I need to use the same values in multiple places; in this case, I need to configure the router's name servers (ip name-server <address>) and ...
4
votes
1answer
489 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 ...
4
votes
1answer
289 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 ...
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
3answers
5k views

How to advertise routes to IPSec tunnels in OSPF using Cisco IOS

I have Cisco 1800 series router (running C181X-ADVIPSERVICESK9-M) with lots of IPSec tunnels. I want to add this router to OSPF and configure it to advertise routes to remote subnets accessible via ...
4
votes
0answers
123 views

IOS QOS service policy pass-through on a tunnel interface

I have some SIP phones on one network that go through an IPIP tunnel to get to the server. I've setup QOS rules to watch for appropriate VOIP traffic as follows: class-map match-any class-voice ...
3
votes
2answers
1k views

What is the Cisco iOS (CLI) command to display a WAP's Radio MAC address?

I can't believe I'm unable to find this with teh g00glez or by RTFMing, but does anyone know how to display the MAC address of a Cisco WAP's Radio (wifi connection) from the command line? show ...
3
votes
1answer
99 views

SMTP errors with iOS devices

I'm trying to diagnose why when an iOS device like an iPhone or iPad is set up to use email with our server for the first time, these errors occur. We choose "Other" from the initial set of choices ...
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 ...
3
votes
3answers
120 views

Show code for specific block in cisco IOS conf mode?

I work with Fortigate gear a lot and in the CLI it's possible to navigate to a node (say config system global then type in show and it will show me the configuration from that block. In IOS I can't ...
3
votes
3answers
2k views

cisco catalyst 2960S, which version of software to upgrade to?

This feels like a dumb question, but here goes. I have a Cisco Catalyst 2960S switch that is currently running software version 12.2(55)SE3 The most current software listed on Cisco's website is ...
3
votes
1answer
1k 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 ...
3
votes
2answers
4k views

Can IOS be upgraded on a Cisco Catalyst 6509 switch without downtime?

There's this Cisco Catalyst 6509 switch with 2 (two) supervisor modules; one of them is active, the other is (almost always) in standby. We need to upgrade IOS; current version is 12.2.something (I ...
3
votes
1answer
969 views

Dual Cisco Router Stateful Firewall

At my company we have a single Cisco 3925sec/k9 router running BGP with 2 ISPs. Now we want to purchase a redundant router of the same model to eliminate a single point of failure. I can set up BGP ...
3
votes
2answers
427 views

Delay NTP Initialisation, Cisco 877W, IOS 12.4(24)T1

I have a Cisco 877W which I'm using for my home ADSL connection (and as a refresher in Cisco IOS). I've got a working config in-place with my PPPoA connection coming online correctly, and VLANs and ...
3
votes
1answer
49 views

Logging commands on cisco devices

I'm searching for a way to log every command executed on a cisco switch/router, I have a catalyst 2960s with lanbase image, and a catalyst 4500e with ipbase image. I've found a way to log commands ...
3
votes
1answer
2k 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 ...
3
votes
2answers
6k views

QoS for Cisco Router to Prioritize Voice and Interactive Traffic

I have a Cisco 891W NATing Voice and Data to the internet over a 10mbit/2mbit connection. Voice traffic gets degraded when I upload large files. Pings time out as well. I tried to configure a QoS ...
3
votes
5answers
7k views

Is there a command in Cisco IOS to show all routes tagged with a specific tag?

In Cisco IOS, if I have a route-map entry as follows: route-map redistribute deny 10 match tag 65000 100 ! Is there a 'show' command that will give me a list of all routes that will match that ...
3
votes
0answers
370 views

strongSwan 4.5.2 with iOS and Mavericks, Connection Troubles

I am having trouble configuring strongSwan 4.5.2 to work with iOS 7 and OS X Mavericks. I have followed these two guides, but am still encountering problems. ...
3
votes
2answers
298 views

Split multicast traffic on two vlans using IOS

Here is what I want to do: On a switch / router running cisco IOS ( Ideally it would work on a Lanbase image on a 3560G but it is possible to use 65xx routers also ) I receive two udp multicast ...
3
votes
2answers
799 views

Cannot ping outside Fa4 on cisco 871w Router (SoHo)

After starting fresh after a write erase and a reload on a cisco 871w. I cannot ping outside of the wan (fa4). I gave vlan1 (default) an ip because apparently the built in "4 port switch" is a layer ...
2
votes
2answers
1k views

Factory Reset my Cisco 1841 Router, Serial cable required?

Is it possible to connect to my Factory Reset Cisco 1841 router without the blue com cable? For instance is there a default IP address I can connect through one of the ethernet interfaces? I just did ...
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 ...
2
votes
2answers
2k views

cisco router loses configuration on reload even after saving it

I'm configuring a Cisco 3640 and it's not saving simple things like my hostname. I've tried with 'wr' and 'copy running-config startup-config'. Also erased the configuration but no luck. There's no ...
2
votes
2answers
6k views

Why do I start at privilege level 1 when logging into a Cisco ASA 5510?

I have created a test user that is set to privilege 15 in the config: username test password **************** encrypted privilege 15 When I log in to the ASA 5510 I am in privilege 1 according to ...
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 ...
2
votes
2answers
1k views

Cisco IOS router config — how to disable SSH / SNMP on all but loopback address?

Sorry for the naive question; a quick reading of the cisco docs doesn't answer this question... So I've got a router (say for the sake of argument a 4500 running IOS 15.x) It has interfaces in 3 ...
2
votes
2answers
4k 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 ...
2
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 ...
2
votes
1answer
205 views

Cisco 7604 router runs out of memory when loading the IOS image, yet runs a different image with similar reqs

I am experiencing an unusual memory issue with a Cisco 7604 router, specifically the memory on the Supervisor Engine (SUP32-GE-3B) and how it pertains to IOS requirements. I was preparing the router ...
2
votes
1answer
149 views

cisco ios - syslog version

I am writing small article on Syslog and I was wondering, if there is any resource that tells me what version of Syslog is supported in what ios version? By Syslog version I mean rfc 3164/rfc ...
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 ...
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,
2
votes
2answers
1k views

Basic IPv6 firewall on Cisco IOS for small network

Now that I have IPv6 connectivity to my network, I'm looking for a basic IPv6 firewall configuration for IOS. It used to be that we could rely on NAT to 'hide' internal (read: outgoing connections ...
2
votes
2answers
1k views

How to determine most stable Cisco IOS release?

This post is about a Catalyst 4948E switch. I was looking on the download page and realized that there are no "GD" versions available. Are the "ED" versions stable? Even if you change "ED" to "GD" ...