Re: OSPF export policy - why is it called an export ?
11-16-2017 04:13 AM
Hello,
It may endure an "import" from OSPF protocol perspective but it is an "export" from JUNOS' Routing Protocol Daemon (RPD) perspective.
The RPD is the JUNOS "brain" that does all shuffling, slicing & dicing of routing information. There are no classify brains for OSPF, ISIS, BGP, PIM etc, it's all done past times principal encephalon called RPD.
Therefore at that spot are 2 principal types of operations RPD does:
1/ import
- it is executed when RPD collates raw information from routing protocol parcel exchanges
2/ export
- when RPD puts "cooked"/processed information into routing protocol packets
Default export/import JUNOS routing policies are explained here
https://www.juniper.net/documentation/en_US/junos/topics/concept/policy-routing-policies-actions-def...
Then JUNOS likewise does an export/import to/from routing instances too routing data bases (RIBs) but let's non acquire into at that spot simply yet :-)
HTH
Thx
Alex
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Juniper PS tin design, examine & induce the network/part of the network equally per Your requirements
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Re: OSPF export policy - why is it called an export ?
11-17-2017 10:45 AM
In Junos, Import policy is used to influence novel routes entering into the primary routing tabular array or rib-local table. Export policy on the other manus is used to export or advertise road existing inward the rib-local table.
Dynamic routing protocols such equally OSPF, RIP, BGP etc. accept a default import too export policy. These default routing policies soundless tin endure altered using customized import too export policy.
For example, the default export policy for OSPF is to non advertise whatsoever routes learned from other routing data sources such equally (statically learned routes or dynamically learned routes through RIP, BGP etc.) to its neighbor. Therefore, for instance if you lot had to advertise a statically learned road to an OSPF neighbor, too thence an explicit export policy has to endure written which would accept to agree the static road too advertise to the neighbor. The same affair would accept to endure done for routes learned through a BGP or a RIP neighor.
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HasanovElshan
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Re: OSPF export policy - why is it called an export ?
11-18-2017 04:47 PM
OSPF Export policy filter External routes to ospf (redistributed from other protocols . LSA5 only) it does non touching LSA3 or LSA4.
The same is ture for Import policy. Do non mix it amongst LSA summarization on ABRs.
BGP import too export policy affects to all the routes accpeted or advertised.
Hope it helps,
Thanks,
Networking or Notworking
https://forums.juniper.net/t5/Junos/OSPF-export-policy-why-is-it-called-an-export/td-p/315667
11-16-2017 04:13 AM
Hello,
It may endure an "import" from OSPF protocol perspective but it is an "export" from JUNOS' Routing Protocol Daemon (RPD) perspective.
The RPD is the JUNOS "brain" that does all shuffling, slicing & dicing of routing information. There are no classify brains for OSPF, ISIS, BGP, PIM etc, it's all done past times principal encephalon called RPD.
Therefore at that spot are 2 principal types of operations RPD does:
1/ import
- it is executed when RPD collates raw information from routing protocol parcel exchanges
2/ export
- when RPD puts "cooked"/processed information into routing protocol packets
Default export/import JUNOS routing policies are explained here
https://www.juniper.net/documentation/en_US/junos/topics/concept/policy-routing-policies-actions-def...
Then JUNOS likewise does an export/import to/from routing instances too routing data bases (RIBs) but let's non acquire into at that spot simply yet :-)
HTH
Thx
Alex
_____________________________________________________________________
Please enquire Your Juniper trouble organisation human relationship squad close Juniper Professional Services offerings.
Juniper PS tin design, examine & induce the network/part of the network equally per Your requirements
+++++++++++++++++++++++++++++++++++++++++++++
Accept equally Solution = cool !
Accept equally Solution+Kudo = You are a Star !
0 Kudos
REPLY
Message 2 of iv (500 Views)
START TECHWIKI ARTICLE
NXTGEN-NE
JUNOS
OPTIONS
Re: OSPF export policy - why is it called an export ?
11-17-2017 10:45 AM
In Junos, Import policy is used to influence novel routes entering into the primary routing tabular array or rib-local table. Export policy on the other manus is used to export or advertise road existing inward the rib-local table.
Dynamic routing protocols such equally OSPF, RIP, BGP etc. accept a default import too export policy. These default routing policies soundless tin endure altered using customized import too export policy.
For example, the default export policy for OSPF is to non advertise whatsoever routes learned from other routing data sources such equally (statically learned routes or dynamically learned routes through RIP, BGP etc.) to its neighbor. Therefore, for instance if you lot had to advertise a statically learned road to an OSPF neighbor, too thence an explicit export policy has to endure written which would accept to agree the static road too advertise to the neighbor. The same affair would accept to endure done for routes learned through a BGP or a RIP neighor.
0 Kudos
REPLY
Message three of iv (389 Views)
START TECHWIKI ARTICLE
HasanovElshan
JUNOS
OPTIONS
Re: OSPF export policy - why is it called an export ?
11-18-2017 04:47 PM
OSPF Export policy filter External routes to ospf (redistributed from other protocols . LSA5 only) it does non touching LSA3 or LSA4.
The same is ture for Import policy. Do non mix it amongst LSA summarization on ABRs.
BGP import too export policy affects to all the routes accpeted or advertised.
Hope it helps,
Thanks,
Networking or Notworking
https://forums.juniper.net/t5/Junos/OSPF-export-policy-why-is-it-called-an-export/td-p/315667
