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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203 views

Cisco IOS: How is it possible to break with default config register of 0x2102

The default config register of an IOS device is 0x2102. The table here clearly states that 0x0100 signifies "Ignore Break," and that the default config register employs these options: Ignores break ...
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1answer
2k views

How to whitelist external access to an internal webserver via Cisco ACLs?

This is our company's internet gateway router. This is what I want to accomplish on our Cisco 2691 router: All employees need to be able to have unrestricted access to the internet (I've blocked ...
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1answer
737 views

Cisco AP, how to show dot11 wpa handshake timeout?

Please help me with a newbie question regarding Cisco AP CLI . According to this Cisco doc , I know how to change WPA handshake timeout value to 2000 milliseconds. Cisco1242AG-1(config)#dot11 wpa ...
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2answers
2k 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 ...
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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 ...
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2answers
2k 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" ...
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1answer
626 views

Can a Private VLAN trunk also trunk normal VLANS

Imagine a topology with Switch A and Switch B trunked together. Also imagine a router on a stick attached to Switch A that routes for these VLANs. The VLANs are as follows: VLAN 1 = 10.1.1.0/24 ...
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1answer
94 views

Using PVLANs with normal VLANs in a trunked environment

Assume a trunked environment with two switches, S1 and S2. The swtiches are connected with a trunk port designed to pass VLAN 26. What would happen if VLAN 26 on S2 is configured as a private-vlan ...
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124 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 ...
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1answer
81 views

Does IOS 12.4 Basic have the “ip nat pool …” available

Could someone with Cisco IOS 12.4 Basic check to see if the command "ip nat pool" is available? We have 12.2 basic and I know it is in the 12.4 advanced version but our budget is very limited so I am ...
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1answer
608 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 ...
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2answers
1k views

Cisco: show run vlan # vs show run int vlan #

What is the difference between the two commands? Show run vlan # = blank output show run int vlan # = vlan configuration Likewise: show vlans No virutal LANs configured show vlan ...
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2answers
2k views

ASA 5540 Enable Password Issue

I have a Cisco ASA 5540 running the following Software/Manager version: Cisco Adaptive Security Appliance Software Version 8.2(2)17 Device Manager Version 6.3(2) I use ASDM to make changes to the ...
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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 ...
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1answer
265 views

Route-map changing from permit to deny retains the match tag values

I have a route-map configured on my cisco router with name say s1 and sequence number 10(default) which contains a match tag 10. If i again try to configure the same route-map name with same sequence ...
2
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1answer
763 views

Cisco Catalyst 4500 Policy Based Routing

In order to test a new firewall I just set up I'm trying to implement policy based routing on our core switch. I want traffic from certain vlans to be routed to the new firewall while everything else ...
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1answer
1k views

GNS3 - Emulating a not supported Cisco router (model 881w)

I want to create a new configuration for a Cisco 881w from scratch. So I want to replicate my environment on GNS3. But I cannot emulate a Cisco 881w (which is the router i have) into it. So I am ...
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2answers
711 views

Cisco IOS PBR - PBRing Skype

I've got a very simple question, which seems to be extremely difficult when put into practice. I have a Cisco IOS router with two Internet links (one over a WAN, through a proxy, everywhere, etc.) ...
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2answers
229 views

What “reachability” means in a routing table?

Check this routing table track 1 ip route 10.46.52.5 255.255.255.255 reachability ip route 10.1.0.0 255.255.128.0 10.243.222.1 track 1 ip route 10.1.128.0 255.255.128.0 10.243.222.1 track 1 ip route ...
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2answers
2k views

Cisco AP Recovery mode - TFTP issue

I am booting without IOS and I get this prompt: ap: then I issue these commands: ap: set IP_ADDR 192.168.0.111 ap: set NETMASK 255.255.0.0 ap: set DEFAULT_ROUTER 192.168.0.1 ap: tftp_init ap: ...
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1answer
2k views

Cisco 881w AP factory reset

If I want to return to the factory IOS and configurations of the AP only, I must issue this command: service-module wlan-ap0 reset default-config right? But which IOS is going to replace the ...
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1answer
264 views

Cisco AP commands dissapeared after IOS downgrade

enter code hereAfter downgrading a Cisco 881w AP (WLAN-AP), something went weird. When I connect on the WLAN-AP interface using: service-module wlan-ap0 session I got this prompt: ...
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2answers
1k views

Configuring a loopback interface on a Cisco router

I have Router 1 with the following interfaces: FA0/1: 192.168.9.193 255.255.255.224 S0/0/0: 192.168.9.129 255.255.255.224 S0/0/1: 192.168.9.161 255.255.255.224 This is for my assignment at ...
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0answers
312 views

Is it possible to embed TCL directly into a Cisco startup-config?

Is it possible to embed TCL directly into a Cisco startup-config? From the (lack of) information I'm finding, it doesn't look do-able. I have a tool that generates Cisco configurations based on some ...
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2answers
866 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 ...
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1answer
2k views

Cisco 3925/k9 sub-interface vlan support

I've got a brand new cisco router 3925/k9. I wanted to set up a router on a stick on my network, but it turns out it doesn't support vlan sub-interfaces. I did it multiple times in gns3 simulator on ...
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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 ...
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1answer
304 views

Cisco IOS subnet mask using bit notation

I was wondering if it was possible to use bit notatiton when configuring interfaces, or just in general, within the CISCO IOS. I have friends and others swear that they've been able to before, but not ...
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1answer
2k views

How to setup a static multicast ARP entry with Cisco SG300?

We're running a Microsoft NLB cluster in multicast mode as a loadbalancer. Using our old Cisco IOS switches we propagate access to the cluster to our branches using a static ARP entry in the core ...
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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 ...
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3answers
8k views

What does the Cisco ASA command “management-access” do?

I'm working with a Cisco ASA 5510. I changed the management interface to a different interface. I used the command "management-access" to get the new interface working, but the old interface ...
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1answer
1k views

Allow my OpenVPN server to work behind a Cisco 800 Router

I have an OpenVPN Ubuntu Server working on ip 192.168.1.11 I need to let my roadwarriors use it from anywhere. I have a Cisco 800 router but I'm not an expert... I've downloaded using tftp its ...
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1answer
3k views

IP SLA on Cisco 1921 IOS 15.2T

Can someone explain to me why I cannot create IP SLA probes on a Cisco 1921 with the latest IOS (15.2T). It is clearly available for that IOS on that router model on the Cisco Feature Navigator ... ...
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1answer
130 views

Cisco 12.4 ACL with DHCP-obtained address

I figured this would be an easy one, but I've had a good amount of trouble finding this answer myself. I have a Cisco router that I'm setting up to have my Internet connection on one interface ...
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1answer
637 views

How to redirect Cisco IOS's show output to HTTP URL?

I found there's a redirect output modifier of Cisco IOS ( version 12.2(53)SE1 ), and there's http: URI support: #sh version | redirect ? flash: Uniform Resource Locator ftp: Uniform Resource ...
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1answer
218 views

Cisco 871 IOS BVI: Distinguishing incoming and outgoing

I understand that a BVI is very much equivalent to a network switch. But it includes the benefit of being able to have an access control list. I am doing this, but I would like to more effectively ...
2
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2answers
7k 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 ...
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2answers
2k views

What characters are illegal in Cisco IOS username secret passwords?

I am using username secret to add users with encrypted passwords to our switches and firewall. I have been battling with the same switches and firewall for a couple of hours trying to get securely ...
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1answer
3k views

How does Cisco IOS ACL established flag work

You can permit outgoing packets, but then you need to permit the responses. One way is to permit any packet that is a followup to an established connection. access-list ??? permit tcp any any ...
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1answer
4k views

How to delete multiple files from a Cisco router flash memory

I have filled up my router's flash with voice files and folders and wanted to remove them. I there a script that can delete all files in flash except for the IOS image?
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2answers
66 views

Can we route video on my redundant link while the primary is up and turn it off if the primary fails over to secondary?

We have a remote location that is currently routing data over a satellite connection. I am adding a cellular fail over if the satellite goes down. I have been asked to install video cameras that ...
1
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1answer
4k views

Cisco IOS port forwarding

I'm trying to forward a port to an inside server. I have tried using static nat to forward it and I have opened it up in the access list as far as I know but I can't seem to get it to open.
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1answer
829 views

How do I setup dynamic VLAN assignment on an autonomous Cisco 1142n?

I've gotten my Cisco 1142n autonomous AP configured with every option under the sun, but I still can't get dynamic VLAN assignment working! I verified the following: I give priority to VLAN ...
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1answer
1k views

Cisco NAT - Sharing single public IP with multiple services

We have this setup on a SonicWall firewall, but I can't for the life of me figure out how to do it on a new Cisco 5520. Here is what I want to do External_IP1:25 --> InternalMailGW_IP:25 ...
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5answers
404 views

Cisco 2811 to Forefront - stop broadcast traffic

I recently upgraded from an old ISA to a Forefront box. I'm now receiving a ton of 0xc0040050 errors. The vast majority are to an internal broadcast address - 100.100.100.255. This is a legacy subnet ...
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1answer
453 views

Forwarding a port internally - Cisco-881

I have a Cisco 881 on which I forward traffic coming from outside to an internal IP, but if an internal IP accesses the external IP, it gets the Cisco HTTP Server (or a broken connection if i set no ...
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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 ...
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2answers
157 views

In which cisco router or IOS verson i can use section command like “show run | section eigrp”

I have seen videos in CBT nuggets for ccnp and ccna. The instructor always uses show run | section eigrp and it looks very good command But i am trying that in GNS , it says command not found How ...
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1answer
216 views

Trunk port wont accept the Printer vlan

I have three switches daisy-chained together and I have a printer vlan serviced with a print server off the core (1st) switch. the middle switch trunk port will not accept the printer vlan. I issue ...
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2answers
446 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 ...