Questions tagged [cisco]

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How should I diagnose why my Cisco ASA denies traffic?

I have a Cisco ASA, which is denying traffic from 172.16.1.5 to 4.2.2.2 on tcp/9000 How can I diagnose why this is happening from the Cisco ASA CLI?
Mike Pennington's user avatar
2 votes
1 answer
558 views

How do I configure an asa 5505 to limit users to only access only company resources and Skype?

I configured an asa 5505 to limit users to only access only company resources and skype. I got skype working but the company sites in the ACLs aren't accessible. What am I doing wrong? ASA Version ...
Michael Ikonya's user avatar
2 votes
3 answers
3k views

Firewalls and ACKs

We have a system using Windows 7 that connects to a piece of equipment directly using a crossover cable on NIC1 and it connects to the network on NIC2. It seems to communicate with everything it is ...
Rafe's user avatar
  • 25
4 votes
3 answers
18k views

Dynamic ARP Inspection ports err-disable with %SW_DAI-4-PACKET_RATE_EXCEEDED

Ports in my network on random switches(connected to Windows 7 workstations) are going into err-disable because of dynamic arp inspection. Ports are going into err-disable because there are too many ...
user4608's user avatar
  • 177
4 votes
1 answer
1k 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 ...
Martin's user avatar
  • 1,229
2 votes
1 answer
12k views

Correct ACL rule to open UDP ports for VoIP

I have the current rules in an attempt to open port 5060 and 10000-20000 for my VoIP provider. We are on a Cisco 1921 router. This ACL is applied to the WAN port on the router facing the ISP. Nmap ...
Kev's user avatar
  • 87
3 votes
2 answers
2k views

Large Number of Received Broadcasts on Layer 2 Interfaces

We are running into a situation where we are seeing a large number of broadcasts received on interfaces that are home to servers. I know this is not normal behavior; ARP cache should remember 100 ...
HAL's user avatar
  • 1,679
1 vote
2 answers
1k views

ISP router unreachable by PAT

I just configured PAT in a router but it doesn't work ,, I write this commands in R1 access-list 4 permit 172.16.0.0 0.0.255.255 ip nat pool AdeNet 80.80.10.20 80.80.10.20 netmask 255.255....
user3423060's user avatar
2 votes
2 answers
12k views

Why does the host in VLAN X flap between ports if LACP is configured?

Aim The aim is to setup LACP. /etc/modprobe.d/bonding.conf alias bond0 bonding options bond0 miimon=100 mode=4 lacp_rate=1 /etc/sysconfig/network-scripts/ifcfg-bond0 ONBOOT=yes BOOTPROTO=static ...
030's user avatar
  • 553
0 votes
1 answer
2k views

Inter vlan can not ping each other

I have this network, but actually pinging between vlans never works. Vlan 10 can ping between its pcs; the same is true for vlan 20, but I can't ping between pcs in different vlans. I don't know if ...
user3423060's user avatar
4 votes
1 answer
584 views

EIGRP to iBGP metric calculation

Consider the following output: router#show ip bgp vpnv4 rd 300:1 5.5.5.5/26 BGP routing table entry for 300:1:5.5.5.5/26, version 538213 Paths: (2 available, best #2, no table) Advertised to ...
knotseh's user avatar
  • 2,535
7 votes
2 answers
5k views

"transport input" for AUX port in Cisco routers

On physical layer AUX port works on asynchronous serial RS-232 protocol. However, one can specify various application layer protocols like telnet or SSH as allowed input protocols under AUX line ...
Martin's user avatar
  • 1,229
3 votes
3 answers
8k views

MAC Flapping on Cisco 2960G

We've been having an issue for the last few weeks on a relatively small network. The issue started when we swapped a specific Cisco 3750 for a 2960G (there were some other changes), exactly since then ...
Thom Seddon's user avatar
2 votes
2 answers
2k views

OSPF route filtering on Vyatta device

We have a connection between our Vyatta Router to our MPLS VPN Service Provider which is a Cisco device. We would like to know how to filter the OSPF advertisement routes on Brocade Vrouter 5400 (...
cgasp's user avatar
  • 2,008
2 votes
2 answers
252 views

List ports which do not have a given property

What would be the easiest was to accomplish this? Find all ports that do not have 'switchport port-security' show run | exclude ? I don't have a swicth with me and packet tracer does not have the ...
mrlayance's user avatar
  • 293
5 votes
2 answers
2k views

Order of entries in "show ip bgp x.x.x.x"

Router# show ip bgp 10.3.3.3 255.255.255.255 BGP routing table entry for 10.3.3.3/32, version 35 Paths: (3 available, best #2, table default) Multipath: eBGP Flag: 0x860 Advertised to update-groups: ...
Eddie's user avatar
  • 15k
2 votes
1 answer
6k views

How do testers (i.e. Fluke) get the port they're connected to?

At work I've been tasked to create a program that acts similar to Fluke testing devices (such as LinkRunners) but will be much more extensive and specific to our needs. One of the capabilities that ...
Kamikaze Rusher's user avatar
2 votes
2 answers
2k views

Redirecting remote-access VPN traffic to BlueCoat web proxy

We'd like to get away from split-tunneling on our remote-access VPNs. The problem I am having is once I turn off split-tunneling, internet bound traffic hairpins on the outside interface without ...
packetologist's user avatar
4 votes
2 answers
2k views

arp inspection with dhcp snooping

My network Figure is : In this figure switch 3750 is my main switch and all of ACL and vlaning and DHCP server and... comands are in this switch. I want set ARP inspection configs for security in my ...
mrb's user avatar
  • 93
3 votes
2 answers
419 views

Cisco BGP Wrong Next Hop

I'm a bit out of my depth with this one & am terrified of making any mistakes. We have two Cisco routers, R1 & R2, configured with BGP. They both have their own internet connections, however ...
NeonMonk's user avatar
2 votes
2 answers
2k views

Cisco ASA 5512 internet connection

I'm new into networking and I have a problem setting up ASA 5512 firewall. The problem is that I can't setup internet connection inside my network. I've created two interfaces WAN with the public IP ...
Vladimir's user avatar
3 votes
2 answers
12k views

Cisco router telnet troubleshooting - connection timeout; unresponsive host

I cannot figure out how to establish a telnet connection between two routers in Cisco Packet Tracer. This is a relatively simple process, I know, but I have been back and forth looking for how to fix ...
Andrew Licharowicz's user avatar
1 vote
1 answer
383 views

Networking, dedicating bandwidth to specific networks

I need to configure a cisco router where 5mb will be split between 2 separate networks one for voice 1mb and one for data 4mb with voice being the main priority. The only way i can think of doing it ...
Dominic's user avatar
  • 11
4 votes
1 answer
2k views

Rate limiting specific IP adresses on Cisco 2960S and 2960X series

We are looking into rate limiting some specific IP addresses down to 5mbit for various bandwidth reasons. Is is possible to rate limit ingress and egress traffic for specific IP addressees on the ...
mastrboy's user avatar
  • 505
0 votes
1 answer
120 views

Three Servers on Three IP's

Hello I'm kind of new to networking and I'm having a small problem of.. not knowing where to start. I have three Windows2012 servers which I would like to assign three IP's from my range given by ...
MrGoodGuy's user avatar
2 votes
2 answers
803 views

cisco Switch Stack Query

Just a small question can we stack poe and non poe switch (2960x)suppose we have 2 non poe and 2 poe switch , then can we stack this Can we make stack of 4
Spei043's user avatar
  • 101
7 votes
1 answer
3k views

BGP authentication-key-chain vs. authentication-key

I found a neat little behavior on a Juniper box I was working with today. We were migrating from a Cisco ASR to an MX and all of our internet exchange peers that had authentication configured didn't ...
Jordan Head's user avatar
  • 7,099
1 vote
1 answer
354 views

ASA 55x - Will management interface shutdown if I remove the IP

I was asked to change the IP address of the management interface on our firewalls but not issue "no ip address" because it will put the interface in shutdown mode which needs to issue no shut again ...
Fanttazio's user avatar
  • 125
4 votes
1 answer
3k views

Replacing Line-Card - Catalyst 6509-E - Questions

I have been handed a ticket to work an RMA for a failed line card in a Cat6509-E. Not ever having worked with these devices before I had a few questions: The config that applies to the ports on the ...
A L's user avatar
  • 3,310
8 votes
5 answers
8k views

Cisco Static NAT with route-maps

Update: Seems that route maps only match on IP addresses, not on the ports. Had another situation this week on a different device, model and software version. Ended up changing the NAT statements to: ...
Firebirdnz's user avatar
3 votes
1 answer
9k views

Cisco router + cable modem - How to configure routing?

I am starting up a small business network. The ISP has provided us two distinct static IP ranges; understand that the actual IP addresses provided by the ISP are in routable Internet space. Network ...
fdmillion's user avatar
  • 181
5 votes
1 answer
1k views

What is the technical reason for PaGP Silent mode and why is it a default?

So I have done a little reading around PaGP silent mode, and I don't understand why it exists. My understanding is from: The silent mode is used when the switch is connected to a device that is ...
Acyclic Tau's user avatar
7 votes
3 answers
25k views

Difference between trunk and access/voice port [duplicate]

Is there a difference between the following two configurations on a cisco device? int g0/1 switchport mode access switchport access vlan 10 switchport voice vlan 20 and int g0/1 switchport trunk ...
koron54's user avatar
  • 71
10 votes
4 answers
191k views

What can cause "FastEthernet is up, line protocol is down" on a Cisco Switch?

I wonder what can cause the first line output of the command show interfaces to be: FastEthernet is up, line protocol is down. In other words, Is the cable that is connected to the local interface, ...
kolxxx's user avatar
  • 101
1 vote
0 answers
6k views

VPN tunnel connection issue

My company has 2 ASA firewall with model 5510 & 5512 in difference country, I was connected it via IPSEC VPN. It can work in normal until 2 weeks ago. I checked from log in ASA5512 firewall, it ...
Man Timothy's user avatar
6 votes
3 answers
24k views

Can Cisco Catalyst switch get IP from DHCP server?

This may be stupid question as I don't have much knowledge in networking. Anyways, I have Cisco Catalyst 2960 switch and I'm curios if I can configure it to get IP configuration from DHCP server, ...
10robinho's user avatar
  • 283
1 vote
3 answers
1k views

Howto configure router to add to private network LAN? [closed]

first I'm gonna warn that I'm fairly bad at understanding networking so kinda nervous about posting this.... I'm using NetsimK to study setting up a network for a college assignment, I'm finding it ...
Paula Taggart's user avatar
4 votes
1 answer
1k views

In a multi-homed BGP network I am looking to create a default route to ISP 1 with ISP2 as backup

I do however, need ISP1 to automatically become the primary route once the route is back up. There are only 3 routers in this topology, router 1 and router 3 are connected with ISP1 and ISP2 ...
Kvothe's user avatar
  • 57
1 vote
1 answer
2k views

Cant access remote management interface

The data link is completely okay. I can access MGMT IPs of routers (10.0.0.2 |10.0.0.4) from 3750 but not from PC. I can access 3750 MGMT IP (10.0.0.1) from PC . Any idea why ? Note : All management ...
eshmam's user avatar
  • 35
2 votes
1 answer
570 views

HW State: DEAD - Cisco 3925

I received an alert stating that a crypto engine was 'dead'. I did a bit of digging and was able to find some output to validate this: #sh crypto eng config crypto engine name: Virtual Private ...
A L's user avatar
  • 3,310
3 votes
1 answer
1k views

CME and 2951 embedded service engine issue

I have a client with CME on a 2951 router. They lost the login creds for CME and I attempted to reset the login via creating a session to the embedded service engine. When I tried to do this I ...
Dave K's user avatar
  • 157
5 votes
2 answers
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 ...
James's user avatar
  • 51
3 votes
1 answer
448 views

Securing Console Serial Ports

I am looking to secure our console ports in our remote console router equipped with HWIC-16A cards and RS232 cables. As the network admins, we usually login to these routers first (using privilege 15 ...
caide's user avatar
  • 31
3 votes
1 answer
13k views

What does 'clear int giX/X/X' do? Cisco

Simple question What functionally happens when executing 'clear int giX/X/X' on a switch? The port config looks the same afterwards, I see no difference.
A L's user avatar
  • 3,310
1 vote
0 answers
88 views

Cisco ASA Hung - Error: "i82546GB/enadap_get: 2 not null"

We configured our new cisco ASA 5520 firewall device to act as RAVPN peer device. AAA is configured in such a way that user will get authenticate at our ACS 5.4 server. After completion of all other ...
Maaraa's user avatar
  • 11
6 votes
1 answer
5k views

Cisco OSPF type 5 /32 routes in database, but not in routing table

Our network runs OSPF for IPv4 on Cisco hardware. The following image shows the relevant topology: Topology Problem Statement We have a Cisco ASA firewall, which also is the VPN gateway for ...
Daniel's user avatar
  • 1,071
5 votes
1 answer
9k views

UDLD state: tx/rx loop detected

Relevant Log messages Feb 1 03:39:08.338 EST: %IPV6-4-DUPLICATE: Duplicate address FE80::212:44FF:FE4D:4400 on GigabitEthernet8/20 Feb 1 03:39:08.904 EST: %UDLD-SP-4-UDLD_PORT_DISABLED: UDLD ...
A L's user avatar
  • 3,310
4 votes
1 answer
2k views

Cisco ACL to block connections with ICMP or RST

The Cisco "deny" ACL seems to quietly drop TCP/IP packets. Is it possible for it to send either ICMP responses or TCP RST's in response to a denied request?
Pablo's user avatar
  • 77
3 votes
1 answer
661 views

Simple egress block ACL on Cisco IOS

I have a Cisco 890 with IOS 15.4. As brief summary of my configuration, FastEthernet 8 is the uplink and NATs the other interfaces (which are grouped into vlan 1). I'm trying to block access to a ...
Pablo's user avatar
  • 77
3 votes
1 answer
1k views

ASA 5525-X PAT only for one IP subnet

Can an ASA 5525-X dynamically PAT one IP subnet of private addresses (from inside port to outside port) and simultaneously pass another subnet through without PAT? I have a public IP address on the ...
Bla bla's user avatar
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