Routing

Dears

Not sure if this is the right behavior or not so would like your assistance please.

I want to match on all loopback /32 prefixes. When I use do this using prefix-list-filter orlonger no matches occur however when i do this using route-filter orlonger there are matches ... Shouldn't both be the same ??

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# Hosts address to be matches as a test 

root@R1# show interfaces lo0 | display set
set interfaces lo0 unit 0 family inet address 20.0.0.1/32
set interfaces lo0 unit 0 family inet address 20.0.0.2/32

# Policy

root@R1# show policy-options | display set
set policy-options prefix-list EGRESS 0.0.0.0/31

set policy-options policy-statement EGRESS_PREFIX_LIST term 1 from prefix-list-filter EGRESS orlonger
set policy-options policy-statement EGRESS_PREFIX_LIST term 1 then accept
set policy-options policy-statement EGRESS_PREFIX_LIST term 2 then reject

set policy-options policy-statement EGRESS_ROUTER_FILTER term 1 from route-filter 0.0.0.0/0 orlonger
set policy-options policy-statement EGRESS_ROUTER_FILTER term 1 then accept
set policy-options policy-statement EGRESS_ROUTER_FILTER term 2 then reject

# Test Reults

root@R1# run test policy EGRESS_PREFIX_LIST 20.0.0.1/32

Policy EGRESS_PREFIX_LIST: 0 prefix accepted, 1 prefix rejected

[edit]

root@R1# run test policy EGRESS_PREFIX_LIST 20.0.0.2/32

Policy EGRESS_PREFIX_LIST: 0 prefix accepted, 1 prefix rejected

root@R1# run test policy EGRESS_ROUTER_FILTER 20.0.0.1/32

inet.0: 10 destinations, 12 routes (10 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

20.0.0.1/32 *[Direct/0] 04:50:47
> via lo0.0
[OSPF/10] 04:50:47, metric 0
> via lo0.0

Policy EGRESS_ROUTER_FILTER: 1 prefix accepted, 0 prefix rejected

[edit]

root@R1# run test policy EGRESS_ROUTER_FILTER 20.0.0.2/32

inet.0: 10 destinations, 12 routes (10 active, 0 holddown, 0 hidden)
+ = Active Route, - = Last Active, * = Both

20.0.0.2/32 *[Direct/0] 04:46:37
> via lo0.0
[OSPF/10] 04:46:37, metric 0
> via lo0.0

Policy EGRESS_ROUTER_FILTER: 1 prefix accepted, 0 prefix rejected

[edit]
root@R1#

Many thanks

Best Regards

Sherif Ismail

Hi !

Your logic is the wrong one as:

root@R1# show policy-options | display set
set policy-options prefix-list EGRESS 0.0.0.0/31

set policy-options policy-statement EGRESS_PREFIX_LIST term 1 from prefix-list-filter EGRESS orlonger
set policy-options policy-statement EGRESS_PREFIX_LIST term 1 then accept
set policy-options policy-statement EGRESS_PREFIX_LIST term 2 then reject

######################

the thing is that your statement as written means:

the first 31 bit of the address has to match the 0.0.0.0 and the orlonger means the mask must be /31 or /32

--- it would only match  0.0.0.1/31 or 0.0.0.0/31 or 0.0.0.0/32 or 0.0.0.1/32

set policy-options policy-statement EGRESS_ROUTER_FILTER term 1 from route-filter 0.0.0.0/0 orlonger
set policy-options policy-statement EGRESS_ROUTER_FILTER term 1 then accept
set policy-options policy-statement EGRESS_ROUTER_FILTER term 2 then reject

#############################

the second one matches everything

##############################

correct in my opinion would be:

set policy-options policy-statement EGRESS_ROUTER_FILTER term 1 from route-filter 0.0.0.0/0 prefix-length-range /32-/32

set policy-options policy-statement EGRESS_ROUTER_FILTER term 1 then accept
set policy-options policy-statement EGRESS_ROUTER_FILTER term 2 then reject

---> this matches any address where the mask is /32

with best regards

alexander

Many thanks Alexander