OSPF is painful

aaron0011

You all that enjoy this are nuts. Whomever came up with all the overlapping acronyms is a terrible person.

DR/BDR/DROTHER
ABR/ASBR
Stubs, NSSA, TSSA, etc.
LSAs for each.

I can't wait to get past this. If you are an all Cisco shop I can't fathom why anyone would want to run OSPF. Just use EIGRP and iBGP if you are too big for EIGRP.

darkerz

I can't tell if this is sarcasm or not.

Also-

Wat?

aaron0011

No sarcasm...perhaps I don't understand it enough and that is my fault but I don't really have a desire too. Necessary evil for CCDP, which is my ultimate goal.

I don't use OSPF at all at work so it's hard to get invested into something you aren't using.

FloOz

It's always a pain learning about something new, especially when that things is as big as OSPF. Over time you'll learn to love it

aaron0011

FloOz wrote: »

It's always a pain learning about something new, especially when that things is as big as OSPF. Over time you'll learn to love it

That's my issue. I know I won't be using it in the near future so mastering and loving it isn't applicable. It's just natural to put less emphasis on something you're not using every day. Also, over time you lose what you don't use when it comes to knowledge.

To me, OSPF is just something I have to learn to pass an exam.

RouteMyPacket

aaron0011 wrote: »

No sarcasm...perhaps I don't understand it enough and that is my fault but I don't really have a desire too. Necessary evil for CCDP, which is my ultimate goal.

I don't use OSPF at all at work so it's hard to get invested into something you aren't using.

lol..that's right..you just DON"T understand it yet and have no experience with it. OSPF is bad @ss!

If you don't understand the pros and cons of OSPF, how can you expect to be a decent network architect? You want CCDP the paper or the skills?

OSPF is no different than anything, you have to have exposure to it. Work with it in a production environment and from there you will see how flexible and awesome it can be.

Do you know the different LSA's and what they do? What is the process the SPF algorithm takes to determine best routes and in which order dos it follow? What happens when you create a NSSA? What happens when you redistribute OSPF into another protocol?

Don't hate, appreciate!

aaron0011

RouteMyPacket wrote: »

lol..that's right..you DON"T understand it and have no experience with it. OSPF is bad @ss!

If you don't understand the pros and cons of OSPF, how can you expect to be a decent network architect? You want CCDP the paper or the skills?

OSPF is no different than anything, you have to have exposure to it. Work with it in a production environment and from there you will see how flexible and awesome it can be.

Don't hate, appreciate!

The Pros and Cons from a design standpoint doesn't mean you have to understand every technical detail. Sure it doesn't hurt but my point is I don't use OSPF at work so it's difficult to be motivated. I'm definitely not trying to become a paper architect.

EIGRP running in GRE through IPSec tunnels for VPN sites and BGP for MPLS works (redistributing as needed) works just fine. Why would I want to change or introduce OSPF when it's not the best option for the network?

I'm much more interested in LAN, Voice, Data Center FWIW, hence my certification path to this point. Those are the technologies I design and support. CCNP/CCDP covers a ton of technology, you don't jane to love them all.

aaron0011

To answer your questions:

It uses bandwidth to calculate the cost/path. O is preferred, then O IA, then Ex Type 1 and Ex Type 2. Runs on a per interface basis (which is cool I admit).

LSAs: Type 1 for Router ID within area, Type 2 Network ID, Type 3 for Inter Area, Type 5 for Redistributed routes with E1 (dynamic cost) and E2 (static cost). I remember type 6 is for multicast and type 7s are similar to 5 but used for NSSA.

Virtual links to connect remote area back to 0 through a different Area. 3 -> 1 -> 0 <- 2 for example.

Familiar with DR/BDR election process and having to use static neighbors depending on if link is broadcast vs non broadcast.

224.0.0.5 address or hellos, LSAs, etc. and 224.0.0.6 for DR/BDR.

I get the basics behind it, just not loving it.

RouteMyPacket

aaron0011 wrote: »

The Pros and Cons from a design standpoint doesn't mean you have to understand every technical detail. Sure it doesn't hurt but my point is I don't use OSPF at work so it's difficult to be motivated. I'm definitely not trying to become a paper architect.

EIGRP running in GRE through IPSec tunnels for VPN sites and BGP for MPLS works (redistributing as needed) works just fine. Why would I want to change or introduce OSPF when it's not the best option for the network?

I'm much more interested in LAN, Voice, Data Center FWIW, hence my certification path to this point. Those are the technologies I design and support. CCNP/CCDP covers a ton of technology, you don't jane to love them all.

But what if your client uses OSPF?

aaron0011

RouteMyPacket wrote: »

But what if your client uses OSPF?

I'm on the customer side. Decent size enterprise.

f0rgiv3n

Of all the networks that I've seen, OSPF is more widely used than EIGRP. So you better get that "OSPF Motivation" from somewhere!

I'm another huge OSPF fan... I'm also an open standards fan... SCREW YOU PROPRIETARY PROTOCOLS!

If you end up going with EIGRP, you're STUCk with Cisco. And chances are high that at some point, someone will insist that you go with another vendor... If you're using EIGRP that just makes it even more of a mess to transition. If you use OSPF it keeps your network a lot more agile.

OSPF +2 Agility

aaron0011

f0rgiv3n wrote: »

I'm another huge OSPF fan... I'm also an open standards fan... SCREW YOU PROPRIETARY PROTOCOLS!

EIGRP is getting an RFC sans the stub option I believe.

DoubleNNs

f0rgiv3n wrote: »

I'm another huge OSPF fan... I'm also an open standards fan... SCREW YOU PROPRIETARY PROTOCOLS!

Didn't EIGRP recently get "re-released" as an open standards protocol? Do you think that other vendors will start to adopt it soon? And if they do, will the argument for needing to learn OSPF start to fade?

darkerz

If EIGRP meets your current needs there is no need to introduce complexity.

...

I would advice learning it enough in case you introduce non-Cisco network infra. 90% of our network is Cisco, but we use OSPF even when its end-to-end Cisco because of TOS routing, tagging, hello packets (the inherently low overhead and multicast'tasticness of it) and it's ability to scale well in a *Data Center setting. Sub-Second convergence is also sexy.

You will NEVER find a scalable or significant multi-tenant DC using EIGRP, only BGP, OSPF, IS-IS or some SDN'ish substitute. For that reason alone, it's good to at least dick around with in in GNS3.

OSPF is really just awesome, dude.

jahaziel

f0rgiv3n wrote: »

Of all the networks that I've seen, OSPF is more widely used than EIGRP. So you better get that "OSPF Motivation" from somewhere!

I'm another huge OSPF fan... I'm also an open standards fan... SCREW YOU PROPRIETARY PROTOCOLS!

If you end up going with EIGRP, you're STUCk with Cisco. And chances are high that at some point, someone will insist that you go with another vendor... If you're using EIGRP that just makes it even more of a mess to transition. If you use OSPF it keeps your network a lot more agile.

OSPF +2 Agility

I believe EIGRP isn't Cisco only anymore.

Cisco Opens Up EIGRP

darkerz

jahaziel wrote: »

I believe EIGRP isn't Cisco only anymore.

Cisco Opens Up EIGRP

This is a cute theory, but it won't come into fruition for awhile.

The RFC draft was submitted, but that doesn't mean non-Cisco infrastructure jumped for joy and immediately released software updates for every iteration released in TCP/IP networks and every company immediately upgraded.

EIGRP is nice in that is supports it's 3 tables and can scale from DC to Edge to Backbone, and back.

EIGRP also needs to get it's act together and support MPLS-TE packets, otherwise it won't gain traction in a SP or DC environment.

RouteMyPacket

aaron0011 wrote: »

I'm on the customer side. Decent size enterprise.

Ok, so let's say later if you work for a VAR and are part of a Design team. You will be designing based on the clients existing infrastructure coupled with what will achieve what they need. In turn, you will run into a ton of OSPF

I'm like you, EIGRP seemed much easier and basic...then I found myself working at a client site and it was all OSPF and here I was supposed to design failover solutions etc. needless to say it really sharpened my OSPF knowledge/skills and it's really cool.

It's just going to be tough if you don't work with it daily, you will have to find it in you to lab out some decent size scenarios (multiple Area OSPF). GNS3 is all you need for that, use loopbacks for your "LAN" segments to advertise.

Danielh22185

OSPF defiantly has its confusing aspects. Yet it is essential to become a master of it if you ever plan to go far in the network world. It is the most diversely scalability IGP protocol, hands down. EIGRP is quick but can't do as much and has scaleability barriers. I work for a very large enterprise and the only areas we use EIGRP are customer end / spoke networks. All of our data centers are fully meshed ibgp running OSPF as the carrier protocol to BGP.

I think we all feel frustrated the same way when we begin to learn something new, especially if it wasn't exactly something we wanted to learn. I always feel in time though something I hate to learn I end up enjoying. OSPF is fun to me now

fredrikjj

Sometimes you need to have some faith and study things even if the purpose isn't apparent to you.

wintermute000

I agree with routemypacket, you gotta be competent on OSPF to be a true R&S networker. In my market, OSPF is much more common than EIGRP. I'd put it at around 4:1 based on my anecdotal observations. Onto SP land and its either OSPF or ISIS core underlying the MPLS. Never EIGRP. If you're a DC enthusiast then OSPF becomes important because its multi-vendor. You're not going to get vendor XYZ's multilayer device / virtual router / whatever running EIGRP are you? But you can bet your bottom dollar it runs OSPF and it runs it more or less 100% RFC compliant.

I know you're a voice guy so I'll pose a rhetorical question: why this sip rubbish mgcp is so much easier

ccnpninja

pain is temporary, knowledge is forever

johnwest43

ccnpninja wrote: »

pain is temporary, knowledge is forever

Best Line ever!

RouteMyPacket

wintermute000 wrote: »

I agree with routemypacket, you gotta be competent on OSPF to be a true R&S networker.

He is going the Design route which IMO means you have to be extremely knowledgable on R/S, SP areas. You won't find a true Sr. Architect that doesn't know routing protocols inside and out. Design is a beast, a completely different game than simple R/S Engineering.

I am far from an OSPF guru but working with multi area OSPF in prod and designing solutions within and around it has helped tremendously.

networker050184

OSPF does have a lot of stuff about it that sucks. Area rules to get around, lack of v6 support in v2, learning the frame relay stuff that you will never use outside of a lab these days. It is the most utilized IGP out there though so if you are serious about working in the networking field you better get used to it.

aaron0011

wintermute000 wrote: »

I agree with routemypacket, you gotta be competent on OSPF to be a true R&S networker. In my market, OSPF is much more common than EIGRP. I'd put it at around 4:1 based on my anecdotal observations. Onto SP land and its either OSPF or ISIS core underlying the MPLS. Never EIGRP. If you're a DC enthusiast then OSPF becomes important because its multi-vendor. You're not going to get vendor XYZ's multilayer device / virtual router / whatever running EIGRP are you? But you can bet your bottom dollar it runs OSPF and it runs it more or less 100% RFC compliant.

I know you're a voice guy so I'll pose a rhetorical question: why this sip rubbish mgcp is so much easier

MGCP is a lazy protocol because it's reliant on CUCM to route calls. Better to control call paths with dial peers on the gateway IMO. I prefer SIP and then H.323 when working with traditional PSTN services like POTS/PRIs. Working with SIP through CUBE is so much more flexible than anything else....and it's easy to see what is going on if there is an issue because you can quickly decipher the protocol with captures.

aaron0011

networker050184 wrote: »

OSPF does have a lot of stuff about it that sucks. Area rules to get around, lack of v6 support in v2, learning the frame relay stuff that you will never use outside of a lab these days. It is the most utilized IGP out there though so if you are serious about working in the networking field you better get used to it.

I already seriously work in the network field...about 10 years now. Like most, earlier in my career I had a lot of sys admin duties as well due to the nature of working in a smaller shop. These days I am in the enterprise strictly doing network but still have a lot of areas to work in. Routing, Switching, Voice, Video, Wireless, Security, VMware, UCS, WAAS, Load Balancers, etc. OSPF is not something I have had to work with before in the real world so it's tough. I'm very aware it's the most widely used IGP but I don't see using it in the near future given where I am employed.

I've done some more labs with GSN3 (4 areas with ASBR to EIGRP Router) since my original post and I'll admit it's cool to see it work but again, hard to become fully invested in something I am not using day in and day out. The pain quote above is cute but you also lose what you don't use.

johnwest43

+1 on losing what you dont use. I am sure I have forgotten at least half of what I had learned about OSPF and EIGRP and 90% of BGP. Glad I took good notes when I was studying for ROUTE!

wintermute000

RouteMyPacket wrote: »

He is going the Design route which IMO means you have to be extremely knowledgable on R/S, SP areas. You won't find a true Sr. Architect that doesn't know routing protocols inside and out. Design is a beast, a completely different game than simple R/S Engineering.

FTW

I did a substantial stint as a design guy in a small provider who leased tonnes of L2 services. Guess what was the IGP.... its amazing how in depth working in a SP forces you to think about R&S. No more thinking in terms of 'BGP into MPLS' (I HATE how enterprise guys 'think' they run MPLS just because they lease a VRF in someone's MPLS-VPN and peer with the PE BGP peer.... you're peering with someone else's L3VPN, thats why its simple ROFL) when you have to understand every L3 hop in the path and no carriers to blame then you really start to appreciate why its important to understand core topics like OSPF in great detail.

I understand the OP's point but I have to disagree with his attitude. Esp. if OP is a designer or arch.
A R&S arch not knowing much about OSPF is like a sysadmin who doesn't know much about vmware - 'but my work uses Hyper V and we have no plans to shift away' ......

maharaliel

Remember that you may meet a scenario where you have some routers that are not cisco routers and this router do not use EIGRP protocols.

Fitzi

maharaliel wrote: »

Remember that you may meet a scenario where you have some routers that are not cisco routers and this router do not use EIGRP protocols.

Not just thinking about non cisco routers, what about non cisco load balancers (F5), wan accelerators (riverbed), proxy servers (bluecoat), or legacy mainframes (IBM) etc, these devices (if L3 is required) will support OSPF or perhaps ISIS but it will be a very long time (if ever) till they have an open and tested implementation of eigrp.

There are many large, all Cisco (R&S) shops unable to run eigrp because of the above interoperability issues. As wintermute000 said it is very different being an enterprise connecting a tail circuit to a provider where you can basically use whichever IGP you see fit, to being under the obligation to support multi tenanted customers and services.

Speaking from my own experience we could never choose a propriety routing protocol (IETF draft not withstanding) as this would limit the equipment and design choice for our customers and our ability to deliver services to them (because of the interoperability reasons listed above). In saying that I don't work for an ISP but we are not a typical enterprise and would probably be classed as a service provider.

On a personal level I don't care what IGP is used in a network (eigrp, ospf, isis) because at the end of the day they all accomplish basically the same thing, reachability. The only reason to choose one over the other would be to take into consideration the skill sets needed to support the chosen protocol, the way I see it the only real differences between them all are implementation and troubleshooting.

aaron0011

Fitzi wrote: »

Not just thinking about non cisco routers, what about non cisco load balancers (F5), wan accelerators (riverbed), proxy servers (bluecoat), or legacy mainframes (IBM) etc, these devices (if L3 is required) will support OSPF or perhaps ISIS but it will be a very long time (if ever) till they have an open and tested implementation of eigrp.

There are many large, all Cisco (R&S) shops unable to run eigrp because of the above interoperability issues. As wintermute000 said it is very different being an enterprise connecting a tail circuit to a provider where you can basically use whichever IGP you see fit, to being under the obligation to support multi tenanted customers and services.

Speaking from my own experience we could never choose a propriety routing protocol (IETF draft not withstanding) as this would limit the equipment and design choice for our customers and our ability to deliver services to them (because of the interoperability reasons listed above). In saying that I don't work for an ISP but we are not a typical enterprise and would probably be classed as a service provider.

On a personal level I don't care what IGP is used in a network (eigrp, ospf, isis) because at the end of the day they all accomplish basically the same thing, reachability. The only reason to choose one over the other would be to take into consideration the skill sets needed to support the chosen protocol, the way I see it the only real differences between them all are implementation and troubleshooting.

Use or have used following.

Riverbed, BlueCoat, even Cisco WAAS (all WCCP redirects and I don't need to be concerned with the IGP with these devices).

Load Balancers (in our case NetScalers) could give two ****s about the IGP in how we are using them.

That said, I am doing my best to learn to appreciate OSPF....and perhaps in a month or two I'll have a different outlook on it. My OP was my first reaction after really diving in. My goal is to complete CCNP R/S by mid summer. I have experience so the learning curve for other topics isn't so bad.