Questions tagged [cisco-ios]
For discussion about Cisco's Internetwork Operating System - Cisco IOS
490
questions
0
votes
2answers
64 views
Restricting TFTP access from Host to Router using extended ACL in Cisco IOS
I am trying the below Extended ACLs to restrict TFTP but still I am able to upload files to the router using tftp. Not sure, what is wrong, can you all help?
Approach 1:
permit udp host <ip> ...
1
vote
1answer
55 views
TCP handshake immediately RST [closed]
I'm trying to set up a modbus TCP connection on port 502 but get a RST packet immediatly. So the TCP connection handshake doesn't even succeed.
This is done on a windows machine on an ESX server.
The ...
0
votes
1answer
38 views
implementing broadcast traffic restriction
Can we restrict the high broadcast traffic from interface in Cisco ASR9k and 7600 routers? If so, what configuration we should apply?
1
vote
1answer
47 views
Filter tagged route to downstream routers
I'd like to filter a redistributed route from EIGRP into OSPF to all routers in AREA2 and AREA34. I have tagged the route 10.90.100.0/24 with tag 90 at the Tampa router where its redistributed into ...
0
votes
0answers
16 views
is crypto ikev2 supported on 1921 router?
is the "crypto ikev2" command supported on Cisco's 1921 ISR g2 router. I'm trying to deploy a site-to-site FlexVPN but the command wouldn't show. I updated the image to c1900-universalk9-mz.SPA.157-3....
0
votes
1answer
40 views
Cisco Zone Based Firewall
I have Cisco 891F configured with ZBF from CBAC. Right now, router is wide-open SSH/443 or anything my public address is listening on, which is not what I intended. My intention was to only allow IMCP ...
0
votes
1answer
20 views
WebAuth With RADIUS For Switch Web Portal
I have a Cisco IE4000 running IOS 15.2. I am trying to login with my RADIUS credentials to the web portal for the switch. Currently the RADIUS is configured for successful login to Console and SSL but ...
0
votes
1answer
39 views
DHCP when you have both layer 3 and switch ports
I have the following config:
ip dhcp pool Vlan10
network 192.168.1.0 255.255.255.0
default-router 192.168.1.1
interface GigabitEthernet0/0
!
interface GigabitEthernet0/0.10
encapsulation ...
1
vote
0answers
63 views
HTTPS QOS and policing
In our office, everything runs on HTTPS. We have softphones and web-based clients which are high priority. We also have Google search, maps and other low priority websites that should work on best-...
0
votes
0answers
52 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
2answers
67 views
What does the Cisco HTTP client (help to) do on a switch?
While checking for vulnerabilities in one of our Cisco switches I came upon this: CVE-2019-12665.
Excerpt from the CVE:
A vulnerability in the HTTP client feature of Cisco IOS and IOS XE Software ...
0
votes
2answers
166 views
Why does yealink ip phone is not getting ip address from voice vlan?
I have configured separate vlan for voip and connected interface to it (as shown below). But the phone is not getting ip address automatically.
switch- cisco 2960-x
phone- yealink
I had tried: (on ...
0
votes
0answers
12 views
Cisco 7960 CTL File Encoding
When booting my 7960 phone, I am getting all of the correct files. However, in trust list (CTL File), the IP addresses are incorrect. They are the ASCII characters of the actual IP address. Therefore, ...
3
votes
1answer
64 views
Moving from 12.x IOS to 15.x IOS - Cisco 3750G
Is there any issue with jumping from IOS version 12.2(35)SE5 to 15.0.2-SE11 on a Cisco WS-C3750G-48PS-S switch?
Should I upgrade to the latest 12.x first (12.2.55-SE12), and then move to the 15.x ...
0
votes
1answer
43 views
Cisco IOS RA VPN with internal NAT
We have a Cisco 871 setup with a remote access VPN which works fine. However we now need the RA-VPN to be able to access an IP on the LAN which only speaks with an authorised subnet. IP addresses as ...
2
votes
3answers
8k views
Reason of “aaa authorization exec default group tacacs+” command in Cisco IOS?
I have a following very minimalistic AAA configuration in ISR router with IOS 12.4(22)T:
aaa new-model
aaa authentication login default group tacacs+ enable
aaa authentication enable default group ...
2
votes
2answers
65 views
How to ping from PC on EIGRP area to PC on OSPF area without middle router?
This is my topology.
And I can send a package to every router and PC within the colored area, how can I ping from a PC on EIGRP area to a PC on the OSPF area? I heard about default route but I saw it ...
0
votes
0answers
29 views
Sending HTTP post request from TCL script running on Cisco IOS
The only way to monitor Cisco's 37XX or 38XX, for example, is SNMP. In some cases, Syslog may be used, too. Arista, for example, provides rich API to pull or push anything to modern monitoring systems,...
2
votes
2answers
139 views
How to ensure startup-config is not changed, building CCIE rack
Let me start with short background for better understanding.
We have LAB at work (Cisco devices mostly), and we would like to allow other employers connect remotely from their homes, build own labs ...
0
votes
0answers
41 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. ...
0
votes
0answers
21 views
Why won't Cisco Catalyst 1760 Router enter rommon?
I have purchased a Cisco Catalyst 1760 Router. It has the password recovery turned off and there is no reset button. I am using ctrl+break in putty on windows to break and it has given me the question ...
5
votes
1answer
2k views
Cisco ASA multiple dynamic VPN support (defaultRAGroup-defaultl2lGroup)
Question (short)
How to set up 2 totally different dynamic l2l vpn tunnels on an ASA5506
Question (extended)
We have a Cisco ASA5506 Security Appliance and we want to set up 2 dynamic VPN setups.
...
2
votes
2answers
58 views
Suppress CLI terminal output on IOS
I would like to know if we can suppress certain lines from being displayed on the CLI. Example: I call following TCL script, that in itself calls some other scripts. What i Get on the screen is this:
...
0
votes
0answers
68 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 ...
1
vote
1answer
67 views
Cisco 860 Disconnecting on WAN port every 30 minutes
I'm completely stuck for solution to this issue. My ISP logs show my Cisco 860 router disconnecting and reconnecting every 30 minutes and 18 seconds all day - it's noticable when browsing as the site ...
0
votes
0answers
32 views
Cisco config deployment, fastest option
I've looked around for an answer, but I just seem to get products or tool ads.
I have 20 routers coming in, which all have the same config (bar IP addresses). What is the quickest way to roll this ...
2
votes
1answer
3k views
How do these NTP authentication commands differ from one another?
A typical Authenticated NTP configuration looks like this:
NTP Server
R1(config)# ntp master
R1(config)# ntp authentication-key 22 md5 SECRET-NTP-KEY
NTP Client:
R2(config)# ntp authenticate
R2(...
2
votes
0answers
58 views
C2960 - Memory has insufficient capacity
Please, do you know if there is any way on how to release more processor memory from a C2960 switch without restarting it?
I am receiving an insufficient memory alarm from this switch. I noticed that ...
0
votes
2answers
50 views
Multiple 802.1x clients, single port support on a Cisco 3750 switch?
I'm thinking of using our Cisco 3750 switch with our RADIUS server for 802.1x authentication on our Ethernet ports.
If I enable 802.1x and a user connects a switch to their Ethernet jack, and the ...
5
votes
1answer
355 views
Hardening Cisco router on Internet-MANAGEMENT PLANE
I need confirmation that I understood the Cisco manual right. So my network is like this:
ISP_RTR ---x.x.x.x/30--- Perimeter/Edge_RTR ---y.y.y.y/30--- FW1 --- DMZ1
...
1
vote
0answers
19 views
Loopback on T1 not showing up
I'm a T1 tech for a major US ISP. We regularly remotely loopback T1s (at the smartjack) and test them before the installation. Recently I got 3 new T1s in a bundle that acted weird, and I hoping you ...
4
votes
1answer
800 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 ...
0
votes
0answers
54 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
2answers
361 views
cisco switch iOS running into problem
I updated Cisco 2960x iOS, but when it started to operate I encountered this error.
"Mar 25 12:02:19.878: %ILET-1-AUTHENTICATION_FAIL: This Switch may not have been manufactured by Cisco or with ...
0
votes
1answer
75 views
How to set vlan QoS priority for voip (on cisco 2960)?
I have assigned all voip-related ports to one vlan. I want to set up the QoS priority for that vlan. Which commands can help and in which mode?
I have assigned all required ports to one vlan. I tries ...
1
vote
1answer
103 views
Understanding Throughput of interfaces problem on Cisco Routers
I have the following topology set on AWS where there are 4 CSR 1000v Routers deployed and Segment Routing enabled in which the Segment Routing Headend is R1 and the destination is R3.
I aim to send ...
0
votes
0answers
38 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
0answers
21 views
Multiple GETVPN groups inter-connectivity issue
Greeting Everyone!!
I'm trying to stimulate an environment where I've DC and DR locations and remote sites have to access DC/DR services.
For security, GETVPN is used. Initially tried using only one ...
1
vote
1answer
35 views
Difference Between PAT with pool or Interface/Loopback?
I'm just wondering what difference does it make when doing PAT with same IP defined in pool or assigning IP on Loopback and overloading that interface.
ip nat pool MYPOOL 1.1.1.1 1.1.1.1 netmask 255....
4
votes
1answer
346 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
144 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?
...
3
votes
2answers
2k views
How do I determine how many routers are in an OSPF area?
Is there any show command which allows me to determine the number of routers in a specific OSPF area? I can use the show ip ospf database router command and consider each LSA represent one router, but ...
3
votes
1answer
73 views
Decreasing SNMP update timer on IOS-XR (CISCO ASR)
I've a case where i'm trying to poll SNMP information every 10 seconds from a Cisco IOS-XR devices (interfaces mib). Seems like CISCO IOS-XR updates SNMP information every 15secs, so sometimes ...
4
votes
0answers
57 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 ...
1
vote
2answers
120 views
Assigning static IP addresses to dialin PPP users on Cisco IOS
I have a Cisco router running IOS 15.3 serving as a dial-in PPP endpoint for a handful of modems. I am using local authentication and a local IP pool to hand out dynamic IP addresses to the callers; ...
1
vote
0answers
122 views
Routes stopped redistributing through OSPF
I was entering a number of secondary addresses on some VLANs. In total there were 10 secondary addresses added.
The subnets added were from three publically routable /24s (I will call them 25.0/24, ...
3
votes
1answer
54 views
Finding MAC address with OUI List
I'm in the process of labeling the interfaces of my Cisco 3750G with descriptions referencing the device type that is associated with that port.
I understand that I am able to run a show mac address-...
1
vote
1answer
189 views
Cisco IOS Version changes for SNMPv3 server-group context
I'm trying to understand switch mapping using SNMPv3. It's come to my attention that the group(user) who is authenticating needs access to thecontext
for mapping out VLANs. I've figures out this can ...
3
votes
2answers
53 views
Firmware Compatibility with 15.x IOS versions
I have a Cisco switch stack with both PoE and non-PoE switches as members. Is there any compatibility issues with the firmware version 15.0.2-SE11 between the following devices?
1x Cisco WS-C3750G-...
4
votes
1answer
423 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 ...
