Well, if you wanted to have different redistribution methods or parameters related to the different processes. Where you usually see different routing tables is in VRF. If you wanted to communicate on a different port or unicast instead of multicast you can configure that under the different processes.
On Jun 30, 2011, at 11:17 AM, Alef <[email protected]> wrote: > I guess i am. Are you saying that different proces id's have access to the > same routes? i.e. if i would advertise one thing in one routing process would > it be available in the other? > > I always thought the opposite. I knew they were different routing processes, > but i also told a aspect of that would be that they would not have access to > eachother's databases. If not, what exactly is actually the point of having > multiple routing processes if there is no particular difference? > > In RIPng, is > ipv6 router rip cisco12 > > also a instance ? > On Jun 30, 2011, at 7:02 PM, Di Bias, Steve wrote: > >> Hey Alef, >> >> I think you're confusing process ID's with instances, they are different. >> >> For example in OSPFv2 you could run multiple processes like "router ospf 1" >> and "router ospf 2" but with IPv6 you can run different instances, for >> example: >> >> Inter s0/0/0 >> Ipv6 addr fd00:BAD:BEAF:BABE::2/64 >> ipv6 ospf 100 area 1 instance 2 >> >> So here the process ID is "100" the area is "1" and the instance is "2" >> >> This might help! >> >> "The Instance ID Identifies the OSPF instance to which this packet belongs. >> The Instance ID is an 8-bit number assigned to each interface of the router. >> The default value is 0. The Instance ID enables multiple OSPF protocol >> instances to run on a single link. If the receiving router does not >> recognize the Instance ID, it discards the packet. For example, routers A, >> B, C, and D are connected to a common link n. A and B belong to an AS >> different from the one to which C and D belong. To exchange OSPF packets, A >> and B will use a different Instance ID from C and D. This prevents routers >> from accepting incorrect OSPF packets. In OSPF for IPv4, this was done using >> the Authentication field, which no longer exists in OSPF for IPv6." >> >> From the IETF >> >> OSPFv3 [OSPFV3] includes a mechanism for supporting multiple >> instances on the same link. OSPFv2 [OSPFV2] could benefit from such >> a mechanism in order to support multiple routing domains on the same >> subnet. The OSPFv2 instance ID is reserved for support of separate >> OSPFv2 protocol instances. This is different from OSPFv3 where it >> could be used for other purposes such as putting the same link in >> multiple areas. OSPFv2 supports this capability using a separate >> subnet or the OSPF multi-area adjacency capability [MULTI-AREA]. >> >> http://tools.ietf.org/html/draft-ietf-ospf-multi-instance-04 >> >> More from the IETF >> >> OSPFv3 >> >> Most of the checks for OSPFv3 are similar to that of OSPFv2. The >> main points of differences are: - >> >> - OSPFv3 runs on a per link basis instead of a per subnet basis. >> The check for network mask is not done. >> >> - Instance ID field (non-existent in OSPFv2) on the link is >> matched with the incoming ID in Hellos. Only if the Instance- >> Id's match do we actually form adjacencies. This allows multiple >> instances of OSPF to run on a single link. >> >> Also check out the following RFC's >> >> http://www.ietf.org/rfc/rfc5340.txt >> >> http://www.faqs.org/rfcs/rfc2740.html >> >> 2.4. Explicit Support for Multiple Instances per Link >> >> OSPF now supports the ability to run multiple OSPF protocol instances >> on a single link. For example, this may be required on a NAP segment >> shared between several providers. Providers may be supporting >> separate OSPF routing domains that wish to remain separate even >> though they have one or more physical network segments (i.e., links) >> in common. In OSPF for IPv4, this was supported in a haphazard >> fashion using the authentication fields in the OSPF for IPv4 header. >> >> Another use for running multiple OSPF instances is if you want, for >> one reason or another, to have a single link belong to two or more >> OSPF areas. >> >> Support for multiple protocol instances on a link is accomplished via >> an "Instance ID" contained in the OSPF packet header and OSPF >> interface structures. Instance ID solely affects the reception of >> OSPF packets. >> >> >> HTH >> >> Thank you, >> >> Steve Di Bias >> Network Engineer - Information Systems >> Valley Health System - Las Vegas >> Office - 702- 369-7594 >> Cell - 702-241-1801 >> [email protected] >> >> -----Original Message----- >> From: [email protected] >> [mailto:[email protected]] On Behalf Of Alef >> Sent: Thursday, June 30, 2011 8:27 AM >> To: [email protected] IE >> Subject: [OSL | CCIE_RS] ospfv3 instances vs ospf proces id's ? >> >> I used to think that you can define as many ospf processes as you like, >> however on the cisco site it states that "unlike ospf v2, with ospv3 you can >> have multiple instances", as if ospv3 is the first to allow this possibility? >> >> is there a difference? >> _______________________________________________ >> For more information regarding industry leading CCIE Lab training, please >> visit www.ipexpert.com >> >> Are you a CCNP or CCIE and looking for a job? Check out >> www.PlatinumPlacement.com >> >> >> UHS Confidentiality Notice: This e-mail message, including any attachments, >> is for the sole use of the intended recipient (s) and may contain >> confidential and privileged information. Any unauthorized review, use, >> disclosure or distribution of this information is prohibited. If this was >> sent to you in error, please notify the sender by reply e-mail and destroy >> all copies of the original message. > > _______________________________________________ > For more information regarding industry leading CCIE Lab training, please > visit www.ipexpert.com > > Are you a CCNP or CCIE and looking for a job? Check out > www.PlatinumPlacement.com _______________________________________________ For more information regarding industry leading CCIE Lab training, please visit www.ipexpert.com Are you a CCNP or CCIE and looking for a job? Check out www.PlatinumPlacement.com
