7. Auto-RP Load Sharing
Now, in this video, we are going to continue with the auto RP, auto RP, load balancing and the load sharing options. So in the previous section, we have configured some RP. We have configured multiple rps like router two and router three. And whenever you have multiple rps, the router is going to select the matting agent is going to select any one of the RP based on the highest IPO. Now, in this scenario, the router three has become the RP. Now, we have seen the redundancy also where we decide to shut down this router three loop back interface. Once I shut down this R three interface automatically, the mapping agent is going to learn the router two as an RP. Now, the one more thing is you cannot use this two rps at the same time.
Now, any one of the RP can work at one time for one particular group address. Now, let’s say if I want to do some kind of load sharing, where I want to use both the rps at the same time, maybe for different groups, what I can do is I can configure something like this. So let’s say I got some two different multicast groups, 224 two two. And I got another group with 224 three. And we can configure the different rps for different groups. Like for the router two will be an RP for 224 two and the route three will be an RP for 224 three. Now, let’s say if I have a server here who is sending a multicast traffic for 224 three, it’s going to register with the router three, because the router three is an RP.
And if I have any client or the receiver who wants to receive the multicast traffic for 224 three, they are going to send the joint messages and the register messages from the source to router three. Now, similar way, if I have any receiver, let’s say I got a source for 224 two, they are going to register with our router two as an RP. And if I have any client who wants to receive the multicast traffic for 224 two two, they are going to send the joint messages to the router two. Now, in this way they can do some kind of load sharing where we are not adding some extra overhead on the RP. And this is something more applicable if you have a very big network and you don’t want to run a common RP for all the groups. We can still do some kind of load sharing, load sharing by using different rps for different groups.
So let’s see how the configuration goes in general here. Now, to make this possible, we need to configure an access list. And in that access list, we are going to define the group address. Like in my scenario, I want to make the router two as an RP for 224 two two. And I want to make the router Three as an RP for 224 three. Now we need to create an access list. And on the router two we are going to advertise IP send RP announced lowback zero and for grouplix ten. So which means whatever the acl, we have used acl ten here another router two will be an RP for 224 two. Two. Because we are defining the acl here a similar way, we are creating one more acl. acl eleven, 224 three. And the router three will be an RP for software group.
So let’s go to the command line to configure the same here. I’m going to router two. Now, already on the router two, we have configured some Pin commands in the previous lab. We have configured the router Two and router three as an RP. I’m going to remove those configurations. I’m going to say no and I’m going to remove the rpm Adasmine. And the default is for all the groups. I’m going to create an access list two permit and it’s going to match 224 two two. And then I’m going to say ipp send, RP announce, send RP announce. The low back zero and the scope is ten. And I’m going to define the group list as two. Now, this will be an RP for whatever the group addresses I define in the acl two. Now, according to acl two, it’s going to be only 224 two.
Similar way, I’ll go to router three and then I’m going to remove the default configurations, what I did in the previous lab, where I configured the router three also as an RP. So I’m going to remove this configuration and then I’m going to create an access list first, which is going to match 224 three. And then I’m going to say ippm send, RP announce, low back zero, the scope is ten for the group list three. And let me clear the mapping information on all the routers because already we have some RP configurations in our previous lab. So I’m going to simply say clear IPIM RP Mappings. And I’m going to do this on all the routers just to overcome those configurations. Let’s do the same thing on the router five as well.
Now on the router four, it is a mapping agent. Already I have configured this as a mapping agent. You can see once I clear the mappings, it is going to delete the mapping information. And now it is going to receive an RP announced for twelve one and it’s going to add for this group 224 two. Router three is an RP and I should receive one more RP information. Let me clear the same thing on the router three, clear IP mappings. Probably when you are making some changes to any RP configurations, I recommend you to use this clear ipm RP mappings so that it can reset all the previous RP configurations. And you can see now once I clear that on the router three, now the router three is going to advertise that 224 three is the RP address is 31.
And if you verify, show Ippim rpm mapping information on the router three four, which is a mapping agent. Router Four is a mapping agent here. And for the Group 224 two. Router two, that is twelve. One is an RP. And for 224 three the router. Router three is an RP. And similar way if you check on any other routers. Like if I say Shuipim RP Mappings. Now I can see here. Let me clear the mapping information here. Clear IP. ppm, RP mapping. I see that old mappings as well. So in the meantime, let me check on the router. Two show IP pim RP mappings. I think I missed this one. So let’s go to router one. And if I use show ipm RP mappings. Now, the Router One. Here you can see for 224. Two.
The RP is Router Two. For 224 Three, R. Three is an RP. So similar Way, if I check the same thing on the Router Two, I should learn this Information. So I’m just verifying the commands are correct or not. So If I go Show I PM Rpmap, it will take some Time, but it will get the same information here. Now, for testing Wise, what we can do is we can we can go to the Router File Interface at Zero by Zero, and we can configure some Join Group commands for 224 Two. Just for testing purpose simulating the Clients, I’m going to join the Group for both the 224 dot Two, dot two dot and 224 dot Three, dot Three. So IP ignp. Join group. Command 224. Dot two, dot two. Dot two. Two. And then I’m going to use Three dot Three, dot three three.
Now for testing wise, I’ll go to router four. Router one. Simulating a router one have some server or the source. And I’ll try to ping to that multicast Address. I should get a reply if everything goes well. And then 224 Three, I should get a reply for that Multicast Group also. Now there’s Something, what we do when it comes to Testing, we are going to simulate a Source and we configure some Join Group commands for the multicast Groups. And if we are getting a reply Messages, it confirms that you are able to send the multicast traffic from the source Receiver. And based on that, it’s going to build some Trees. We are not getting a trees here. Like to verify that we can use Show ipm route. I can see it’s going to build a multicast.
Three S commercial entries in the multicast routing table. Now this way we can provide some load sharing Options. Now, if you want to combine these two features in this scenario, as I have configured Router Two as an RP for this group Address, and in case if that Router Two goes down, then there is no fallback option because we did not configure any fallback options. So if you want to configure a fallback option. It’s recommended to configure the access list something like this. If you verify in the access list, we have configured saying that it only matches this address, it’s always recommended to add access list to permit. We can define the remaining address range like 224 dot, zero, zero. And then I can define the different group purposes.
Now, which means now I’m going to add one more statement show Access list where I’m going to define specifically 2240 zero, two. And then I’m going to match all the remaining addresses. All the remaining addresses belonging to all the remainders belong to D class here, class D here. Now, similarly, the same thing I’m going to do in this particular access list. I’m going to say access list three, permit 2240 zero and then 15 dot 255-25-5255. Now, in my network and if you verify the configurations here, let’s verify the configuration along with this acl show on include pin. I’m just verifying the configurations and then access list. Now, if you just try to observe here the configurations, we are going to write that for the group three, router three will be an RP, right?
And in case if that particular RP goes down due to some reason, it’s going to fall back as an RP, which means now in case now in this scenario, what we’re are saying is the router three is an RP for 224 three. And it’s going to be the backup for the remaining groups. That’s what we are going to define here. And similarly, the same thing on the router two, we are going to say that if I verify the configuration, show run include pin. And then if I verify the access list here now here, I’m going to say that for this group, address 224 two, it’s going to be an RP. The router two will be an RP for 224 two. And it’s going to fall back for the remaining addresses. So whenever you’re writing the acl for any group, it’s going to see the shortest match.
Now in this scenario, it’s going to see this match here, like here. If you verify the confirmation on the router three, router two is going to define all the class D addresses here. And on the router three, all the class D addresses here. But there is a specific match here. So you’re going to use 224 three as an RP here. Now, if that particular RP fails, now what I’m going to do is I’m going to shut down the RP here. Assuming that the RP goes down due to some reason, I want to make sure that the router two should take up the role of an RP here. Now, if I check Show IP RP mappings and if I try to clear the mapping information so I just cleared the IP mapping information here and I’m expecting some of the messages coming up.
Now, if you just observe here, I just clear the clear IP rb mappings on all the Routers, just to make sure that all the Routers clear the rb mapping Information. Now, If I try to observe the debug Output debug ipp motorp on the mapping Agent that is on the Router Four, it receives the RP announced for Two D four Two Two, and also it is building the mapping for the remaining Addresses. And the reason is because of the access list here. Now, on the Router Two, if I give show access List, I have defined that Router Two is an RP for this Address. And on the Router Three we have defined the Router Three is an RP for 224. Three. Now in case if the Router Three RP goes down, it should fall back to the backup. RP. Now, in my scenario, the backup RP is R two for this group address if you verify on the router one if I verify the RP mapping information.
Now Here You can see It’s aridizing the mapping information for 224 dot Two, dot Two, dot Two. Router Three is an RP at the same Time for all the remaining Groups. Remaining groups means in my scenario, 224 dot three dot three dot three also comes under this category because the router three is already down, where we have manually defined router three as an RP for this one. So the primary RP will this. If that goes on, it will fall back to the second one. Now, If I try to ping to the Multicaster statuses 224 Three, dot Three, I should get a Reply still and also I should be able to reach 224 two Two. And this way we can provide some redundancy. Now, if you want to have some Redundancy as well as Load Sharing, probably it’s recommended to Configure Some isil, something like this.
Now there are three options. We have Seen in the previous Video, we have seen how to configure Redundancy by using separate Two different rp’s. If you configure Router Two and Router Three as an RP, it’s going to select the Router Three based on the highest ipos. Or we can configure Something called Load Sharing with for an RP where we can configure saying that 224 Three. For this group, router three will be an RP. And for the other group, like 224 two two. We can say router two is an RP, or we can combine these two features in one again. So if you want to combine these Two Into One, we need to create an acl which is going to match that particular Group. And if that particular group address is not reachable, whatever the RP we have configured, it will fall back to the default group address.
8. PIM Bootstrap Router
In this video we’ll talk about Pim bootstrap router which is an alternate native to auto RP for rodising the RP information to the rest of the domain. Now, pimboostop router is a standard based protocol which is a part of the Pim versions to standard. And one of the major advantage with the Pim bootstrap router is it’s a standard based solution to advertise the RP information within the Pim domain. And also it supports ipv six multicast. Now, the functionality is going to be the same as auto RP. And here also it is going to define two different rules where we need to configure any specific router as an RP, we call it as an RP candidate and the bootstrap router the same concept as mapping agent. Now here the RP candidate is going to same as candid RP in the auto RP.
But the major difference between the auto RP and the bootstrap router is auto RP is going to use some multicast addresses like 239-0139 and 40 to listen to the RP announced and mapping agent discovery messages. So RP announced and RP discovery messages. Now instead of the information here it is sent, it is flooded in the form of pin messages or behalf. Now here whatever the RP candidate let’s say in my scenario, I’m going to make these two routers an RP or any one router as an RP. Now this RP is going to use a unicast to advertise itself to a bootstrap router and there is no more multicast addresses required. But in case of auto rpv they need to register to those multicast addresses in order to get the RP information.
But here the candidate RP uses unicast to autodize itself as the candidate RP and then the bsr candidate is going to propagate this information to the rest of the domain hop by hop in the actual Pim messages. So it’s not going to use any, it just includes the information about the RP in the pin messages hop by hop. It’s going to be a little bit easier simplified way to advertise the RP information. And also it is a standard based. Now configuration wise also it’s going to be very easy. Whatever the router we decided as an RP we need to go to that router and we need to tell Ipfem RP candidate and loop back zero interface. And then you can make the same router as a mapping agent or bsr router.
We call it as bootstrap router or you can make any other router as a bootstrap router here. So in my scenario I’m going to make the router three which is the RP as well as the bootstrap router. Now, once we configure this, all the routers are going to learn about the RP information and that is something I would ask by the bootstrap router in the actual name messages. So let’s get into the command line to verify this configuration. Now, the first thing I got an igp configured in my osp of domain using on all the fire routers using osp of area zero. So that’s the first step. And also all the routers are pre configured with IP pim spars mode. Now, these are the two prerequisite pre configured things I have in this initial configurations here.
So if you want to verify we can specifically go to router specific routers like let’s go to router four to verify the information here. So the first thing on the router four I have osp of neighborship and also if you verify show IP pim neighbors. On the router four I got three pim neighbors and similar way I can go and check on the router two osp of neighbor and then show I p pim neighbors. And if you verify the routing table, I can see all the routes advertised as per the topology, all the connected interfaces are advertised here. Now, the next thing is what we are going to do is the next thing we we are supposed to configure an RP here. Now, this time I’m going to make router three lowback zero as an RP and also I’m going to make the router three as a bsr candidate also.
So bootstrap router. So I’m going to make the router three as a bootstrap router. So let’s configure this before I configure, I’m going to enable the debug command debug IP pim on one of the router just to verify the messages here I’ll go to router one, route three, I’m going to say IP pim RP candidate loopback zero. Now, before we enable this command, we are using loopback zero and show that particular loop bag zero is already enabled with IP pim spark mode. Now here I did that already. If you just check the interface, it is already preconfered and also the loadbag zero is already advertised in my ospf domain.
So if you just verify this IP ospf interface brief, the loopback zero is also advertised here. Now, there’s something already preconfered here. So the next thing what I’m going to do is I’m going to make the router three loopbag zero as an RP. We got some additional parameters we can change later on we’ll get into these options. Right now we’ll go with simple configuration and then we are going to say IP PM bsr. Can it also loop back zero. So if you verify show IP pim rpm mappings. Now, this system is a candidate RP as well as it’s a bootstrap router. I can see it receives a bootstrap portion two message from 13 one. I’m expecting some more messages here.
You can see on the client side under auto one, I have enabled this. Let me clear the pin. Maybe if I have some rpp RP information. Now, if you observe here, bootstrap forwarded on router one. Now, if you just verify here on the router four, if I go show Ippim RP mappings, you can see for by default we did not define any group. So it’s going to be for all the class J addresses. Now the RP is 31, the router three low back interface and it’s learned via bootstrap. And if I go and check on the router one, you can see I have a debug message here. Received a bootstrap on this interfaces and you can see the RP information has been learned for this group address via Pim version two.
And if I go show ipm rpm mapping, I can see that RP information. The RP is 31 for the complete class T addresses and it’s learned via bootstrap program. Now, to test the readability, I have configured on the router one, router five. If you just get into the interface of zero by zero, I have pre configured some group igmp join group messages on the router five. Let’s go to router one and try to ping to those group messages to 24 two two. I should be able to reach that particular group purchases so that they’re going to confirm that let me disable the debug gear and then I should be able to reach that particular group purchases. And if I try to ping to 224 three that is on the router file, I got some join messages I’m able to reach.
I can see here there is no more multicast addresses used in case of auto RP. The RP candidate as well as your mapping agent has to learn the information via multicast addresses. But whereas in case of bootstrap router it’s going to use some unicast Pin messages to advertise itself as itself as an RP to the psr. So it’s going to be unicast. And then the psr is going to include the RP information in the Pin messages. Now it’s going to provide the unfim information to the rest of the mine, which allows all the remaining routers to learn about the RP information so that they can send some joint messages and the register messages.
