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1500 questions
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5 answers

Connecting two different Cisco Switches using Fibre

I have two Cisco Catalyst 2960-24TC-L switches and would like to connect them using fibre over a distance of 200Meters. According to cisco, the switches has two SFP ports, which I can clearly see on them but my issue is I do not know where or how to…
Laredo
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How are the LERs determined in an MPLS LSP using LDP

Preface; In the below topology R1 and R6 are PEs, all others are P routers, all routers are running c7200-jk9s-mz.124-13b.bin. At this point IGP is fully converged (OSPF with all interfaces in area 0 for simplicity) and MPLS is enabled on all…
Baldrick
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Splitting two Internet connections between two VLANs

My current setup is as follows: Cisco 881 router (only 1 WAN interface) that has a pair of T1's coming in on the WAN interface, this currently provides internet access to two VLANs, 10 and 20. What is changing: We are adding another pair of T1's,…
David Rediger
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3 answers

Broken PPPoE Config

We have been struggling with this for a few weeks now. CISCO 3825 (15.1 IOS) with properly established PPPoE (ie can ping the net from inside the cli). The problem we are having is that the client's cannot ping the outside world. I have the client…
Nick Cameo
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1 answer

Is it possible to use single MAC address for multiple IPv4 addresses?

Topology: modem with router and Ethernet LAN bridge <---> server having one NIC. Server network interface: It is capable of handling more than one IPv4 address. All addresses are within the same subnetwork. Modem: Does the routing service and…
user2964971
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8
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3 answers

10Gig over single strand fiber

We have several BX SFPs in my network and I love them. We're limited on the amount of fiber we can get between buildings (each pair costs $250/month) so the mismatched laser solution gives us redundancy and extra bandwidth all at once. For the…
Avery Abbott
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Dealing with IP Spoofing

Border routers, which are routers that span two or more sub networks, can be configured to block packets from outside their administrative domain that have source addresses from inside that domain. Source: Introduction to computer…
Henok Tesfaye
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Is the shaping-rate on a CoS scheduler per-port or aggregate on a Juniper EX?

I'm using a Juniper EX2200 as demarc/CPE device for a customer that has multiple handoff ports on the one switch. I need to make sure that, across all their ports, they don't use more bandwidth than they ordered. I've read the Juniper doc Defining…
jda
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SubInterface on a router

How many sub interfaces can be created on a cisco router to route between vlans on a connected switch?
Benk4c
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1 answer

What is VLAN Hopping

I am starting on my journey into the world of Networking and have come across a term called VLAN hopping. The sentence I read was that if the Native VLAN on two switches connected to each other via their trunk interfaces had different Native VLANs,…
Tismyselfsure
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How to failover static ipsec vpn tunnels?

I have a network with resilient gateways whereby Customer sites use a default gateway to reach the internet edge routers and the primary route for traffic uses a lower metric. ipsec tunnels are initiated from vpn concentrators behind the edge…
MattE
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Factors that determine compatibility of SFPs with new fibre services?

Whilst I understand that product recommendations are off topic can anyone help by explaining what the critical factors are when looking for SFPs that are going to be compatible with a new service? Is wavelength a defining factor that should be…
MattE
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1 answer

Are the SFP/SFP+ int's on WS-X45-SUP7-E autosensing?

I have two Cisco Catalyst 4510R+E systems that I am interconnecting, using the interfaces on the sup's (both have dual Sup7-E's.) They are marked 1G/10G Uplinks (SFP/SFP+) on the sup above the interfaces. I have ordered 10G SFP+ modules, but in the…
Will Dennis
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What is the expected behaviour of the ARP cache?

I am familiar with the arp cache being relative to the default age timer regardless of whether a packet has been seen or not and that the router should refresh entries by sending an update arp request before the default 240 mins have expired in…
MattE
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Are ICMP Redirect messages really bad?

Due to potential for MITM attack, ICMP redirect messages should be blocked. However, the original purpose of the ICMP redirect message is to inform the host of a better router (or gateway). Then, is there a speed issue with disabling ICMP redirect…
baeharam
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