LISP + GETVPN as alternative for DMPVN+OSPF+GETVPN
Originally LISP was developed to address the issues and concerns raised by the growth of the internet routing table, but LISP turns out to possess appealing features that can be of interest to Service Providers like my friends at InTouch.At the Cisco NAG2010 conference in San Jose I talked about using LISP as a transport mechanism instead of regular manual GRE tunnels or a DMVPN design. I believe that provisioning and debugging a LISP based virtual private network will be easier and simpler than current approaches.
Some fair warnings are in order here: this setup runs on beta IOS and NXOS images, this design and the configuration syntax are very likely to change a little with every IOS release, for Cisco's LISP implementation is under very active development. The most important aspect of this design is that it's not a multi-tenant architecture. Multi-tenancy will probably be available in a few months, after which I'll post an updated version with more comments on the specifics.
View the slides online at slideshare: LISP+GETVPN or download the PDF from my website: Job_Snijders-InTouch-LISP_GETVPN.pdf.
Ticket #16
Ticket #16 is published under the CCIE Flyer. Click here for direct link. Enjoy!libvirt & KVM & unnumbered bridge setup
This is an ubuntu/debian recipe to use an 'unnumbered bridge' to save on the amount of IP addresses needed to connect your virtual machines on a libvirt host to other networks.I'm assuming you want the host to be a router between the VM's and the external network. The advantage of this is that you can firewall traffic between the virtual machines and other networks on the host.
A setup like this can be used if your ISP provides you with a /29 and you want to be able to use every IP address out of that /29, and not waste IP's on the network, broadcast and gateway address.
This image shows the various elements involved:
The /etc/network/interfaces file on the host:
auto virbr0The above configuration will configure a bridge interface without an IPv4 address and route the /29 that was assigned to you by your ISP to that interface. This will force Linux to ARP for every IP from that /29 on this particular virbr0 interface.
iface virbr0 inet manual
bridge-ports none
bridge_stp off
bridge_maxwait 1
post-up ip route add 10.10.10.0/29 dev virbr0
The following virsh commands will remove the default network settings, you can Continue reading
Ticket #15 – Repubished
I am reposting here Lab 15, which was published on ccieflyer.com. Next ticket, Ticket 16, which will be about IP services will be published on CCIEFlyer.com, then it will be republished here again. ...The network was configured with multicast-helper to transport the RIP broadcast over the multicast network to R6.T-Minus One Week!
That’s right, I’m taking the 640-802 exam from Cisco to attain my CCNA (Cisco Certified Network Associate) certification in one week! The last four weeks have been quite eventful, although I’m ashamed I didn’t really start studying REALLY hard until about 3 weeks ago. Regardless, I’ve learned a lot! I’ve been following the book “31 Days Before Your CCNA Exam”, which is essentially a daily planner for study topics regarding CCNA material.T-Minus One Week!
That’s right, I’m taking the 640-802 exam from Cisco to attain my CCNA (Cisco Certified Network Associate) certification in one week! The last four weeks have been quite eventful, although I’m ashamed I didn’t really start studying REALLY hard until about 3 weeks ago. Regardless, I’ve learned a lot! I’ve been following the book “31 Days Before Your CCNA Exam”, which is essentially a daily planner for study topics regarding CCNA material.Cogent (AS174) does not have a full ipv6 table yet
As of date Cogent (AS174) still has not entered into a peering agreement with Hurricane Electric (AS6939), resulting in significantly less prefixes than most IPv6 transit providers will give you. I've compiled a list of prefixes that are missing in Cogent's table.Most IPv6 transit providers will give you roughly 3500 prefixes, but Cogent only carries around 2500 prefixes.
If you want to be reachable from all over the world over IPv6, it's best to get a second and third IPv6 transit provider that give you a full IPv6 routing table. In other words, avoid having a Cogent-only network.
txt file: ipv6-prefixes-that-cogent-misses-as-of-27-Oct-2010.txt
Solaris as an Open Source alternative to Linux
When I left Solaris after the Sun/Oracle marger, it was because I wanted to try some new things in life possibly based on OpenSolaris. I had led Solaris in networking and network virtualization space for a long time and wanted to make a bigger mark in that space compared to what Oracle might have wanted. But my hope was that Solaris as a Open Source Operating System would continue to prosper and I could possibly use OpenSolaris as a base for whatever I decided to do next. Well, the exodus from Solaris has continued over the past few months and now Mike has also decided to call it quits. Mike was one of my counterparts, running the storage side of the house (other leaders in storage and filesystem space, like Jeff and Bryan had already bailed out of Solaris few months after I left).
So at this point, I am forced to consider the fact that Solaris and OpenSolaris are on the brink of death unless something serious is done about it. Having spent so much time and energy in last 15 years on Solaris (including bringing it back from life after the last tech bust when Solaris had been Continue reading
Raw IP Traffic Export (RITE) on Cisco IOS
Often, especially in medium to large networks, it’s crucial to monitor the traffic traversing your networks. Those in the networking industry know that tools like tcpdump and wireshark are crucial for deeply investigating network issues. Even developers use these tools to diagnose issues with applications utilizing network resources. Many times, it is helpful to install/use one of these tools to figure out exactly what’s traversing the network, by seeing the frames and packets themselves, in a visual way.Raw IP Traffic Export (RITE) on Cisco IOS
Often, especially in medium to large networks, it’s crucial to monitor the traffic traversing your networks. Those in the networking industry know that tools like tcpdump and wireshark are crucial for deeply investigating network issues. Even developers use these tools to diagnose issues with applications utilizing network resources. Many times, it is helpful to install/use one of these tools to figure out exactly what’s traversing the network, by seeing the frames and packets themselves, in a visual way.IS-IS Single-Topology vs Multi-Topology
Today I’m covering a little topic that seems to trouble some people. Mainly because IS-IS is really only used in provider environments, but I happen to like it. It’s a fairly stable...[[ Summary content only, you can read everything now, just visit the site for full story ]]
compilation of internet exchange memberlists
I'm compiling a list of internet exchange member lists. Please help expand the compilation by contributing urls to public CSV, TSV or files in other formats!You can find it here: Internet Exchange memberlists
DTAG (AS3320) seems to not prefer customer routes by default
I noticed that DTAG's best path selection differs from most transit suppliers I know. Most transit providers will prefer routes received from their customers above routes they receive from peers. This type of policy ensures that traffic will flow over the most profitable links. It seems that DTAG on the other hand, by default, assigns a local preference value of 100 to every route they receive through eBGP.It could mean that DTAG is actively turning down money by not filling up links that are sold on a 'per mbit' basis. Also, it could lead to confusion, which I'll try to explain with the following example:
You are AS65001, you buy transit from AS65555. You have a sister company (AS65002) with which you swap your full routing table. That sister company buys transit from DTAG (AS3320). DTAG and AS65555 peer with each other. AS65002 will announce the routes originated by AS65001 to DTAG.
DTAG now has to choose between two paths: a 'peering' path 65555_65001$ and a 'customer' path 65002_65001$. Both paths by default will have a local preference value of 100. So if for some reason the 'peering' path is chosen (because it's older, or the router-id of that Continue reading
Location / Separation Protocol Checklist
This list can be useful when assessing LISP, ILNP, RANGI, Ivip, hIPv4, NOL, CRM, LMS, GLI-Split, TIDR, EEMDP or IRON-RANGER. :-) Location / Identifier Separation Checklist:Your post advocates a
( ) technical ( ) legislative ( ) market-based ( ) vigilante ( ) political
approach to reducing the growth of the internet routing table (e.g. the DFZ). Your idea will not work. Here is why it won't work. (One or more of the following may apply to your particular idea, and it may have other flaws.)
( ) Requires immediate total cooperation from everybody at once
( ) There is no centralized authority that will force people to carry out your plan
( ) Requires every host to be upgraded to a newer version of their netstack
( ) Nobody wants to rewrite all applications to support your plan
( ) your mapping system consumes more memory then available on planet earth
( ) New complicated IP allocation policies must be set by the RIRs
( ) People won't give up their current allocations
( ) Your plan is incomplete or contains too much "needs to be further discussed." phrases
( ) No one can agree Continue reading
eBGP triggered blackhole for customers
Very many large scale transit providers, if not most of them support eBGP remote triggered blackhole via separate multihop eBGP session. I suspect this is, because they've used for very long time single shared route-map for transit customers, and it is not immediately obvious how you can support blackholing without customer specific route-map. Requiring customer specific route-map would probably be less than minor change in their provisioning systems. However, it is perfectly doable and same idea works just the same in JunOS and IOS, here is pseudoIOShy example how to do it:
router bgp N
neighbor eBGP peer-group
neighbor eBGP route-map eBGP-IN in
neihgbor eBGP disable-connected-check
neighbor CUSTIP peer-group eBGP
neighbor CUSTIP prefix-list C-CUSTID-IN in
!
route-map eBGP-IN permit 100
match community BLACKHOLE
set ip next-hop BLACKHOLE
set community BLACKHOLE additive
route-map eBGP-IN permit 200
match ip address prefix-list eBGP-TRANSIT-FULL
set community full-transit additive
route-map eBGP-IN permit 300
match ip address prefix-list eBGP-TRANSIT-PARTIAL
set comunity partial-transit additive
route-map eBGP-IN permit 400
set ip address prefix-list eBGP-PUNCHOLE
set community no-export additive
!
ip prefix-list C-CUSTID-IN permit 192.0.2.0/24 le 32
ip prefix-list C-CUSTID-IN permit 10.10.42.0/28 le 32
ip prefix-list eBGP-TRANSIT-FULL permit 192.0.2.0/24
ip prefix-list eBGP-PUNCHOLE Continue reading
Re: A High-Level overview of LISP
This is a response to Petr's well articulated discussion of LISP: "A High-Level overview of LISP"
He captured some of the key points that make LISP compelling, including the discussions about hierarchical routing (and associated problems with address allocations and multi-homing), the "level of indirection" enabled by LISP - due to the separation of host addresses (EIDs) and routing locators (RLOCs) - and the "push" vs. "pull" aspects of various mapping and routing systems.
There are a several areas that I think deserve greater explanation, however. The most important is regarding the LISP mapping system. "Core routing table size reduction" was the initial focus (and instigation) of LISP. But core routers are not the only ones taking full routes, some people might want the full routing table to be available on more places to have more granular control over egress traffic. Because BGP is a "push" technology, the FIB must be populated with full routes and be available in the "forwarding path" (data plane) of packets. This leads to the need for expensive silicon and memory on each line card. Where LISP helps is in two main areas. First, the LISP ALT routing table is decoupled from expensive Continue reading