Stack Exchange Network

Stack Exchange network consists of 175 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

Questions tagged [routing]

For questions about routing, the process of selecting to which network path traffic is sent. Consider using a more specific tag if your question is about a routing protocol like BGP or OSPF.

3
votes
1answer
3k views

Routing table in QNX [closed]

I've an embedded system running on QNX 6.2.1. (I'll call it QNX box.) The QNX box has two network adaptors. I've configured the driver, so they appear as en0 and en1. Here are their IP settings: en0:...
7
votes
1answer
1k views

Reliable connectivity to China

I have been struggling on getting reliable connectivity to China (AS4837 China Unicom Backbone, AS4134 China Telecom Backbone, AS4538 China Education and Research Network Center) On most links I have ...
10
votes
3answers
4k views

Inbound BGP load-balancing from same ISP router

I have two BGP routers for DIA with an issue with one provider in that the two links to this provider land on the same SP router. My ethernet handoffs via two separate MetroE links from another ...
4
votes
1answer
3k views

Isolating Juniper Management Plane

Out of the box, it seems that the Juniper management routing is part of the default route table. Can I use logical systems to isolate the service plane from management routing? Are there any drawbacks?...
4
votes
2answers
845 views

Setting the same gateway address at a DR site as our main site

I have a question about routed traffic across a site to site VPN between 2 Cisco ASA 5510's. We have our office side and our DR side and the question is could I have an IP conflict of gateway IP ...
12
votes
2answers
2k views

RIP routing is broken between two routers

There are 2 routers connected something like this: Network1 ----- (172.16.1.1/24) Router 1 (172.16.3.1/30) ------ (172.16.3.2/30) Router 2 ------ (172.16.2.1/24) Network 2 I try to add addresses for ...
21
votes
3answers
3k views

CEF operations on L3 switch vs router

I understand that L3 switches use CEF for faster packet forwarding. However, CEF will not work for packets that need to undergo NAT. Does this mean CEF isn't used by edge routers and edge L3 switches? ...
10
votes
3answers
666 views

Circular BGP propagation

This one is a difficult to describe, it's hypothetical because I'm learning about routing and right now I'm focused on BGP. Let's say my ASN is 65000, and I announce 192.0.2.0/24. My peer, AS 65001 ...
10
votes
3answers
7k views

Default-network and default-gateway

When would you choose to use the ip default-network command instead of the ip default-gateway command?
8
votes
1answer
7k views

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 talking about a DC design or ...
4
votes
2answers
1k views

Is migrating to VRF or rolling-back an easy proposition?

If VRF is implemented for routing table separation such as having an overlay network for a guest network that doesn't mix with regular LAN routing, is migrating to it easily done on Cisco switches (...
6
votes
6answers
1k views

What are the reasons for choosing separate or combined VPN and Internet routers?

Here's a network design question: I've just been reading "IPv6 for Enterprise Networks" by McFarland et. al. and it (among other Cisco documents) separates out Internet routing from remote access VPN. ...
8
votes
3answers
171 views

How to apply configuration after replacing Routing Engine(RE) for CISCO7609-S?

Senario: I have the backup configuration file. But I don't any USB drive or compact flash card. After replacing the Routing Engine, I tried to copy/paste the configs (around 12k lines) from the ...
12
votes
1answer
1k views

What is the difference between a VRF and GRF? (cisco)

I've heard about VRF's and GRF's, but was is the difference between those 2? (cisco)
3
votes
7answers
9k views

Dynamic Routing Protocol (IGP) over IPSec VPN tunnels to branch offices?

What are the best practices for running an IGP to learn networks at HQ from branch offices when those offices connect via IPSec LAN-to-LAN VPN tunnels over the Internet? The branch offices terminate ...
12
votes
6answers
3k views

Best practice for dual-homing site with two ISPs?

I am subscribed to two ISPs, a fast expensive one and a cheap but slower one. They use different technologies, cable and ADSL, so there isn't much of a single point of failure, and all my comms ...
9
votes
1answer
286 views

Remote Campus Routing Design

A third party provider supplies connectivity my remote satellite campus over metro ethernet. Due to red tape the provider is required to supply a routed point-to-point connection (R2 and R3) to the ...
9
votes
3answers
14k views

Cisco: prevent vlan's of communicating with eachother on cisco router (ACL alternative)

Setup: Cisco router with multiple VLAN's configured on it. How can you prevent 2 VLAN's communicating with eachother? Normally I would do this with ACL's like this: access-list 102 deny ip 1.1.1.0 0....
7
votes
2answers
3k views

VPN routing for hosts with multiple ip addresses [closed]

I use Mikrotik RouterOS as the NAT router. Some hosts behind the router also have a direct connection to the Internet and these hosts have a default route to the ISP's gateway instead of RouterOS. I ...
16
votes
7answers
91k views

What are the differences between VRRP and HSRP?

Are there any significant differences between VRRP and HSRP?
20
votes
7answers
30k views

Difference between access list and prefix list?

Can someone explain with an example whats the difference between an access list and prefix list.
8
votes
3answers
6k views

BGP - Soft Reset Outbound & Verification

My understanding of the command: clear ip bgp * soft out is that the router on which the command is issued will re-advertise everything it knows about BGP to it's neighbors. As I see it, it's as if ...
37
votes
8answers
27k views

How would a router with /32 WAN subnet mask communicate with the rest of the Internet?

I'm studying networking and one of the most basic things I've been told countless times is that computers can't communicate outside of their own subnet. On the other hand, by looking at some ADSL ...
11
votes
2answers
3k views

Why don't iperf, scamper and path MTU discovery packet captures agree on the path's MTU?

Let's do some path MTU discovery between two Debian hosts separated by a Debian router that runs Shorewall-generated iptables rules. Each of the two hosts uses a single Ethernet link while the router ...
8
votes
2answers
24k views

Policy routing configuration in Fortigate

I have an scenario where a Fortigate firewall is used to separate internal networks from the Internet (FortiOS Version 4.0 MR3 patch 11). Right now there is a single Internet connection attached to ...
7
votes
4answers
9k views

Distributing static routes across an OSPF area

If you have a router which does not support OSPF, but your routing topology makes use of OSPF as all other devices do support it, what is the best way to get this routers networks in to the OSPF area? ...
10
votes
3answers
1k views

Routing with seperate WAN link for backups

We have two geographically separate data centers. We are preparing to implement a new WAN connection (dark cloud) that would be used only for backup traffic. The servers will have two NIC cards (...