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<p>Hi colleagues,</p>
<p>suggest me, pls, where to look for the solution to the issue.
Ubuntu 22.04, frr 8.5.2, router configuration is below<br>
</p>
<p>Upon start and during some time everything is ok, but for some
reasons after the time the following happens (reduced output) and
can be fixed with 'clear ip ospf proc' :</p>
<p>While FRR RT is ok:<br>
</p>
<blockquote type="cite">
<p><i><font face="monospace"># sh ip route<br>
[ ... ]<br>
O 0.0.0.0/0 [110/10] via 100.64.98.3, blue, weight 1,
01:34:12<br>
via 100.64.99.3, orange, weight 1,
01:34:12<br>
B>* 0.0.0.0/0 [20/0] via 212.113.51.33, wan, weight 1,
1d00h30m<br>
C>* 100.64.0.0/23 is directly connected, br-int, 1d00h30m<br>
O>* 100.64.2.0/23 [110/20] via 100.64.98.2, blue, weight
1, 01:34:13<br>
* via 100.64.99.2, orange, weight
1, 01:34:13<br>
O>* 100.64.4.0/23 [110/20] via 100.64.98.3, blue, weight
1, 01:34:13<br>
* via 100.64.99.3, orange, weight
1, 01:34:13<br>
O 100.64.97.0/24 [110/10] is directly connected, wg0,
weight 1, 01:34:24<br>
C>* 100.64.97.0/24 is directly connected, wg0, 1d00h30m<br>
</font></i></p>
<p></p>
</blockquote>
<p><br>
</p>
<p>Linux RT lacks 100.64.2.0/23 and 100.64.4.0/23 -</p>
<blockquote type="cite">
<p><i><font face="monospace"># ip route<br>
default nhid 229 via 212.113.51.33 dev wan proto bgp metric
20 <br>
100.64.0.0/23 dev br-int proto kernel scope link src
100.64.0.1 <br>
100.64.97.0/24 dev wg0 proto kernel scope link src
100.64.97.1 <br>
</font></i></p>
<p></p>
</blockquote>
<p><br>
</p>
<p>Issuing if 'clear ip ospf proc' solves the issue - these routes
appear in Linux RT again, until next time.</p>
<p>It's always ok with OSPF neighborship - hello packets are
reaching all destinations (tcpdump confirms this :-) ) :</p>
<blockquote type="cite">
<p><i><font face="monospace">vishnu.utc.mygaru# sh ip ospf neigh<br>
Neighbor ID Pri State Up Time Dead
Time Address Interface RXmtL
RqstL DBsmL<br>
100.64.2.1 1 Full/Backup 17m52s
3.823s 100.64.98.2 blue:100.64.98.1
0 0 0<br>
100.64.4.1 1 Full/DR 22m59s
3.403s 100.64.98.3 blue:100.64.98.1
0 0 0<br>
100.64.2.1 1 Full/Backup 17m52s
3.823s 100.64.99.2 orange:100.64.99.1
0 0 0<br>
100.64.4.1 1 Full/DR 22m59s
3.403s 100.64.99.3 orange:100.64.99.1
0 0 0<br>
</font></i></p>
<p></p>
</blockquote>
<p><br>
</p>
<p>and following daemons are running with the following arguments -</p>
<blockquote type="cite">
<p><font face="monospace"><i>root@vishnu:~# ps ax |grep frr</i><i><br>
</i><i> 816287 ? S<s 0:18 /usr/lib/frr/watchfrr
-d -F traditional zebra bgpd ospfd staticd</i><i><br>
</i><i> 816303 ? S<sl 0:05 /usr/lib/frr/zebra -d
-F traditional -A 127.0.0.1 -r</i><i><br>
</i><i> 816308 ? S<sl 0:06 /usr/lib/frr/bgpd -d -F
traditional -A 127.0.0.1</i><i><br>
</i><i> 816315 ? S<s 1:19 /usr/lib/frr/ospfd -d
-F traditional -A 127.0.0.1</i><i><br>
</i><i> 816318 ? S<s 0:03 /usr/lib/frr/staticd -d
-F traditional -A 127.0.0.1</i></font><br>
</p>
<p></p>
</blockquote>
<p><br>
</p>
<p>The only information I see in the log is the following:</p>
<p>This is restart of the ospf process:<i><br>
</i></p>
<blockquote type="cite">
<p><i>Aug 9 18:45:03 vishnu ospfd[816315]: [T08NC-EWX63][EC
134217741] Link State Acknowledgment: Unknown Neighbor
100.64.4.1</i><i><br>
</i><i>Aug 9 18:45:03 vishnu ospfd[816315]: [T08NC-EWX63][EC
134217741] Link State Acknowledgment: Unknown Neighbor
100.64.2.1</i><i><br>
</i><i>Aug 9 18:45:03 vishnu ospfd[816315]: [X7SPE-Y4BTR][EC
134217741] Link State Update: Unknown Neighbor 100.64.2.1 on
int: orange:100.64.99.1</i><i><br>
</i><i>Aug 9 18:45:03 vishnu ospfd[816315]: [X7SPE-Y4BTR][EC
134217741] Link State Update: Unknown Neighbor 100.64.2.1 on
int: blue:100.64.98.1</i><i><br>
</i><i>Aug 9 18:45:03 vishnu ospfd[816315]: [X7SPE-Y4BTR][EC
134217741] Link State Update: Unknown Neighbor 100.64.2.1 on
int: blue:100.64.98.1</i><i><br>
</i><i>Aug 9 18:45:03 vishnu ospfd[816315]: [X7SPE-Y4BTR][EC
134217741] Link State Update: Unknown Neighbor 100.64.2.1 on
int: orange:100.64.99.1</i></p>
<p></p>
</blockquote>
<p><br>
</p>
<p>and a bit later, but I don't know whether this relate to the
issue and whether they appear at the same time:</p>
<blockquote type="cite">
<p><i>Aug 9 18:57:41 vishnu zebra[816303]: [RG2NH-FTSDH][EC
4043309102] Kernel deleted a nexthop group with ID
(300[253/254]) that we are still using for a route, sending it
back down</i><i><br>
</i><i>Aug 9 18:57:41 vishnu zebra[816303]: [RG2NH-FTSDH][EC
4043309102] Kernel deleted a nexthop group with ID
(280[234/235]) that we are still using for a route, sending it
back down</i><i><br>
</i><i>Aug 9 18:57:41 vishnu zebra[816303]: [RG2NH-FTSDH][EC
4043309102] Kernel deleted a nexthop group with ID (276[])
that we are still using for a route, sending it back down</i><i><br>
</i></p>
<p></p>
</blockquote>
<p><br>
</p>
<p>The question - any suggestions where to look for the solution to
the problem? Which additional information I need to gather which
can help solve it? May be I'm missing something in OS
networking/kernel configuration? (I, actually, wasn't tweaking
configuration except ip.forward=1). Will appreciate any
recommendations on this.</p>
<p>Thank you.<br>
</p>
<p>~~~~~~~~~~~<br>
<font face="monospace">frr version 8.5.2<br>
frr defaults traditional<br>
hostname vishnu<br>
log syslog informational<br>
no ipv6 forwarding<br>
service integrated-vtysh-config<br>
!<br>
interface blue<br>
description === Blue infra ===<br>
ip ospf dead-interval 4<br>
ip ospf hello-interval 1<br>
no ip ospf passive<br>
exit<br>
!<br>
interface orange<br>
description === Orange infra ===<br>
ip ospf dead-interval 4<br>
ip ospf hello-interval 1<br>
no ip ospf passive<br>
exit<br>
<br>
! this is eBGP to ISP<br>
router bgp NNNN<br>
[ ... ]<br>
exit<br>
<br>
!</font><font face="monospace"><font face="monospace"> this is
eBGP to ISP<br>
</font>router bgp 64512 view erspan<br>
[ ... ]<br>
exit<br>
<br>
!<br>
router ospf<br>
ospf router-id 100.64.0.1<br>
passive-interface default<br>
network 100.64.0.0/23 area 0<br>
network 100.64.97.0/24 area 0<br>
network 100.64.98.0/24 area 0<br>
network 100.64.99.0/24 area 0<br>
network 192.x.x.x/24 area 0<br>
default-information originate<br>
exit<br>
<br>
! few these prefix lists used for BGP<br>
ip prefix-list [ ... ]<br>
!<br>
end<br>
</font><br>
</p>
<pre class="moz-signature" cols="72">--
Volodymyr Litovka
"Vision without Execution is Hallucination." -- Thomas Edison</pre>
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