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9 votes
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What's the difference between Serial DCE and Serial DTE link?

One side of the link (DCE), has to transmit the clock signal, which controls the data rate, and the other side (DTE) receives the clock signal. R1 is DCE here: interface Serial0/0/0 ip address 10.0....
jonathanjo's user avatar
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9 votes
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Different Behaviour of a Router

You don't have to add anything in the 1st case because it's automatic. As there's only one router, it obviously knows everything directly connected to it. When that becomes more than one router, some ...
Ricky's user avatar
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9 votes

Different Behaviour of a Router

Why in the first case, There was no need of adding Routing table Because it's not really true that there was no need of adding a routing table. When you configured the IP addresses and subnets of the ...
AndreKR's user avatar
  • 191
7 votes

missing Packet tracer physical Tab

Try select Option from menu bar, click "Preference", switch to "Hide" tab and uncheck the "Hide physical tab" box. Hope this helps.
randomguy's user avatar
6 votes

Why can't two hosts (in two different logical networks) connected to each other through cross-over cable communicate?

A host knows if the destination address is on a different network (the same way that you do, by masking the host and destination addresses with the host mask). If the destination is on the same ...
Ron Maupin's user avatar
  • 99.9k
6 votes

Why aren't mac addresses of a serial port shown on packet tracer

Serial ports don't have or need MAC addresses. It's as simple as that.
Marc 'netztier' Luethi's user avatar
6 votes
Accepted

delete object network in cisco ASA with packet tracert

It's giving you that/those error(s) because removing that object would leave the access-list empty but still existing, which is not possible or allowed, and you can't delete an access-list like that (...
Jesse P.'s user avatar
  • 4,690
5 votes

All OSPF routes lost when interface fails

The message you got is perfectly normal. That is not OSPF crashing, but it is telling you that the neighbor is no longer there. The interface is down, so OSPF cannot communicate with that neighbor. ...
Ron Maupin's user avatar
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5 votes
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OSPF - Default route doesn't get advertised to all areas

1. The first issue is that you configured same Router-ID (RID) router-id 1.1.1.1 for R1 and R2 in area 45. All OSPF router should have different RIDs across the OSPF network domain. 2. And the ...
Hung Tran's user avatar
  • 3,754
5 votes
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Multiple access lists on same vlan

You can't have more than one access list per direction on an interface. So, to accomplish this, you will have to create a unique access-list for each interface that allows only the traffic you want.
Ron Trunk's user avatar
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5 votes
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Show interfaces brief information

The most common commands are show interfaces show ip interface brief Or for a specific interface show interfaces vlan 1
jonathanjo's user avatar
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5 votes

What's the difference between Serial DCE and Serial DTE link?

DCE stands for data circuit-terminating, data communications, or data carrier equipment - this is a modem or more generally, a line adapter. DTE stands for data terminal equipment which generally is ...
Zac67's user avatar
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5 votes
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What is wrong with this set of routers?

R2's default route points back to R1. Instead it needs to point to R3 via Serial0/0/1.
Zac67's user avatar
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5 votes

Why aren't mac addresses of a serial port shown on packet tracer

MAC Addresses are specific to Ethernet interfaces - serial interfaces are point-to-point and use a different Layer 2 protocol (PPP, HDLC, FR etc.) for communication. EUI-64 is most likely deriving it'...
Benjamin Dale's user avatar
5 votes
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Default gateway of host connected to two routers via switch

Because you have not a star-shaped network, you have to define a route to reach each network. Your routes can be : 192.168.2.0/24 via 192.168.1.254 Default via 192.168.1.253 or 192.168.2.0/24 via ...
redheness's user avatar
  • 166
5 votes
Accepted

inconsistent bad mask error

The mask you were trying to use really is a bad mask. You were trying to use 255.255.225.248. You simply had a typographical error that you eventually corrected. It happens, and it is a big reason ...
Ron Maupin's user avatar
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4 votes
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How to sniff a switched LAN by plugging the laptop into a switch port

The easy part: Use Wireshark for the sniffing. The hard part: In a switched network you need support from the switch to get all the traffic. It is called "port mirroring", "span port", "monitor port" ...
Sebastian Wiesinger's user avatar
4 votes

DHCP Server giving the wrong IP address and DHCP server failed Apipa being used

It appears that some of your ports are in VLANs that do not have ip helper addresses on the router. They won't get addresses from your server.
Ron Trunk's user avatar
  • 67.7k
4 votes

Can we run Linux guest OS in Cisco Packet Tracer?

Packet tracer is a simulator unlike GNS3 which is an emulator. so you cant run linux guest os in packet tracer
Pravin's user avatar
  • 39
4 votes
Accepted

Understanding Cisco standard access lists (Packet Tracer example)

Ping is an application that is bidirectional. It sends an ICMP request, and expects an ICMP reply. You have broken the traffic from one direction, so you cannot ping either direction (one way the ...
Ron Maupin's user avatar
  • 99.9k
4 votes
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Can I connect a PC to a router directly in Packet Tracer?

You'll need a crossover cable to connect two MDI devices without auto-crossover. The switch presents MDI-X. https://en.wikipedia.org/wiki/Medium-dependent_interface
jonathanjo's user avatar
  • 16.3k
4 votes
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Issue with ACL and router on a stick network

With this ACL: ip access-list extended IT_SEGMENT permit ip 10.1.10.0 0.0.0.31 10.1.30.0 0.0.0.31 ! You are limiting traffic coming in from that interface to only the 10.1.30.0/27 network because ...
Ron Maupin's user avatar
  • 99.9k
4 votes

How can I ping with source option in Cisco Router?

You can use the ping command for choosing Extended commands options: Router#ping Protocol [ip]: Target IP address: 10.0.12.1 Repeat count [5]: 10 Datagram size [100]: Timeout in seconds [2]: ...
aircraft's user avatar
  • 1,138
4 votes
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IPv6 can't ping host when static route configured with exit interface

Remember that IPv6 doesn't use ARP. There is no broadcast on IPv6, and ARP uses broadcast. IPv6 uses ND, which uses multicast. Notice the difference in the route configurations: ipv6 route 2004::/64 ...
Ron Maupin's user avatar
  • 99.9k
4 votes

i cant configure the ip adress and subnetmask ,i only have one router "1941" and 2 pc's

You misspelled "address". Using the tab-completion feature on most devices usually helps with spelling errors :)
jim's user avatar
  • 85
4 votes
Accepted

Get DHCP IP with subinterface

You cannot have two interfaces in the router with addresses in the same network. You didn't define a different VLAN for GigabitEthernet0/0 than the native VLAN, so it will try to get an address in the ...
Ron Maupin's user avatar
  • 99.9k
4 votes
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Let connections go through a server to a router in packet tracer

Cisco Packet tracer is CCNA Level Simulation software. Therefore it does not support advanced features. If you want to do advanced level configuration, you have to use GNS3. It will support ...
infra's user avatar
  • 3,128
4 votes
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Why does the Implicit Rule prevent traffic from passing?

I have seen this countless times when one configures explicit ACL's on interfaces. By default, if there exist exactly zero access control lists, the ASA will freely PERMIT all traffic from higher ...
sietecFAST's user avatar

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