Network Engineering Stack Exchange
Network Engineering Stack Exchange

Most Popular

more tags
1500 questions
10
votes
5 answers

What layer of the OSI model deals with ports?

I've read that the session layer is also called the ports layer, and a CBT nugget video implied ports were a layer 5 thing. I always thought they were layer 4, just because I guess. (well and tcp and udp have the ports) Strangely I don't get much…
Ralph Pocky
  • 113
  • 1
  • 1
  • 5
10
votes
2 answers

load balance between two ISP bgp links

I have up-links to two separate ISPs on one router and receive a default route from each via BGP. Both links are the same speed and BGP is used only to advertise our prefixes out. Whats the best way to load balance across the two links? It was…
phesen
  • 103
  • 1
  • 5
10
votes
4 answers

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, but not connected to the far end switch causing…
kolxxx
  • 101
  • 1
  • 1
  • 4
10
votes
4 answers

Setting up DHCP server on the router or on the switch?

We're using the Cisco 1921/K9 with a SG300 L3 switch. Does one set up DHCP server on the router or on the SG300? If both is capable, what is the reason to choose one over the other? Note: I have 4 VLANS set up on the SG300 L3 switch
lamp_scaler
  • 655
  • 2
  • 7
  • 15
10
votes
2 answers

Cisco DMVPN Phase 3 Question

I was hoping that someone might be able to shed some light on a problem I'm having. I have a lab that I created that is a multi-region Hub and Spoke network. There are 5 Regional Hubs along with one central hub. Each Region has 4 spokes. My problem…
Ryan
  • 101
  • 3
10
votes
1 answer

Firewall Replication

If I have two datacenter sites that are considered redundant to each other. Is it possible to sync firewall configuration from the primary to the backup? What is the best way to keep both firewalls updated at the same time? If so, what is…
user1477
  • 223
  • 1
  • 5
10
votes
4 answers

converting AP from CAPWAP to autonomous - BVI1 interface gets reverted back to DHCP

Has anyone ever gotten this message in the middle of converting a CAPWAP access point from CAPWAP to autonomous? *Mar 1 00:47:59.399: %CAPWAP-3-STATIC_TO_DHCP_IP: Could not discover WLC using static IP. Forcing AP to use DHCP. This has popped up…
knotseh
  • 2,535
  • 4
  • 24
  • 35
10
votes
4 answers

Embedded routers vs. software routers in the datacentre

I've been looking for a new 'core' router to put in our new rack which is colo'd at a nearby datacentre. What I've come across is the usual Cisco/Juniper/Brocade lineup, with the usual unattractive price points; and I wondered what would happen if I…
Libbux
  • 515
  • 3
  • 14
10
votes
3 answers

DHCP assign IP address based on MAC address with Cisco CE 500 platform?

I have very little knowledge about CISCO and its switches, but now I have to configure it myself. Is it possible to allot IP address based on MAC address on CISCO CE 500 (Cisco Catalyst Express 500-24TT Switch [WS-CE500-24TT] )switches ?
kaushik
  • 203
  • 1
  • 5
10
votes
4 answers

PIM-SM multicast and HSRP/VRRP

I need to set up a PC to listen in on a multicast (PIM-SM) data feed. The multicast sources and (anycast) Rendezvous point are behind a "HSRP/VRRP address" on the other side of a WAN link. (The instructions actually say "HSRP/VRRP") As per the…
Gerben
  • 4,690
  • 20
  • 32
10
votes
3 answers

Default-network and default-gateway

When would you choose to use the ip default-network command instead of the ip default-gateway command?
Adam Loveless
  • 3,129
  • 7
  • 30
  • 51
10
votes
1 answer

What factors drive L2 vs L3 in the access layer?

When designing an access layer, best practices today seem to indicate going toward a L3 design. I know the answers may be different depending on whether or not we're talking about a DC design or Enterprise Campus design. Please describe when you…
generalnetworkerror
  • 7,104
  • 6
  • 32
  • 66
10
votes
1 answer

What's the difference between CRS-1 and CRS-3

What are the differences between the CRS-1 and CRS-3 platforms? I know the CRS-3 is the upgrade to CRS-1. Do I need a new chassis to upgrade to CRS-3? Or is a CRS-1 chassis upgradable to a CRS-3 just upgrading the RP, MSC and Fabric cards? What is…
Brown Taylor
  • 453
  • 1
  • 4
  • 11
10
votes
3 answers

Why one of the pairs on Ethernet is not adjacent?

I know that Ethernet over twisted pairs have two standards as the figure below: The pairs are twisted to avoid cross-talk. But why in both standards there is one pair that is not adjacent (pin 3 always pairs with pin 6)? Once I have got a wrong…
Vinicius Tinti
  • 203
  • 2
  • 5
10
votes
3 answers

What is the use of a tunnel interface on a cisco router?

What is a tunnel interface used for on a cisco router? What is the difference between setting up a VPN connection and a tunnel interface; or does this serve the same purpose?
Bulki
  • 2,383
  • 7
  • 25
  • 44
1 2 3
…
99 100