<html><head><meta http-equiv="content-type" content="text/html; charset=us-ascii"></head><body style="overflow-wrap: break-word; -webkit-nbsp-mode: space; line-break: after-white-space;">Hi All,<div>I have a working OSPFv2 session in Full state, between bird and <a href="https://www.flocknetworks.com/non-wp-content/docs/flockrs/21.1/ospfv2/ospfv2-component.html">flock</a>. On restarting the ospf session from bird, while it is already in full state, following log messages were seen, which claims that bird had received a LSA with invalid checksum from flock. After a brief troubleshooting session with the flock developers, it was found that bird complains about an LSA that it itself had originated and sent to flock earlier. Flock doesn't modify anything in the LSA and sends it back in the LSUpd when it receives a LSReq </div><div><br></div><div>Here 1.1.1.1 is flock and 100.100.100.100 is bird</div><div><br></div><div><div><font face="JetBrainsMono-Medium" style="font-style: normal;">2023-03-02 10:07:30.421 <TRACE> ospf1: HELLO packet received from nbr 1.1.1.1 on bird-0-0-L</font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">2023-03-02 10:07:35.318 <TRACE> ospf1: LSREQ packet sent to nbr 1.1.1.1 on bird-0-0-L</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">2023-03-02 10:07:35.318 <TRACE> ospf1: length 36</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">2023-03-02 10:07:35.318 <TRACE> ospf1: router 100.100.100.100</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">2023-03-02 10:07:35.318 <TRACE> ospf1: LSR Type: 0001, Id: 100.100.100.100, Rt: 100.100.100.100</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">2023-03-02 10:07:35.322 <TRACE> ospf1: LSUPD packet received from nbr 1.1.1.1 on bird-0-0-L</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">2023-03-02 10:07:35.322 <TRACE> ospf1: length 64</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">2023-03-02 10:07:35.322 <TRACE> ospf1: router 1.1.1.1</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">2023-03-02 10:07:35.322 <TRACE> ospf1: LSA Type: 0001, Id: 100.100.100.100, Rt: 100.100.100.100, Seq: 80000003, Age: 2101, Sum: 1984</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">2023-03-02 10:07:35.322 <RMT> ospf1: Bad LSA (Type: 2001, Id: 100.100.100.100, Rt: 100.100.100.100) in LSUPD</span></font></div><div><font face="JetBrainsMono-Medium" style="font-style: normal;">2023-03-02 10:07:35.322 <RMT> ospf1: received from nbr 1.1.1.1 on bird-0-0-L - </font>support@flocknetworks.com</div></div><div><font face="JetBrainsMono-Medium" style="font-style: normal;"><br></font></div><div>I have attached the full ospf logs from bird and the ospf packet captures using tshark along with this. Can someone have a look and check if it is possible for bird to generate LSA with wrong checksum?</div><div><br></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">Bird config:</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">============</span></font></div><div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">log "/var/log/bird.log" all;</span></font></div><div><br></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">router id 100.100.100.100;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"><br></span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">protocol device {</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> scan time 10;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">}</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"><br></span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">ipv4 table table1;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"><br></span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">protocol bfd bfd_bird {</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> interface "*" {</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> interval 0 us;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> multiplier 3;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> };</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">}</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"><br></span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">protocol ospf v2 ospf1 {</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> area 0.0.0.0 {</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> networks {</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> 10.100.1.0/24;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> };</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> interface "bird-0-0-L" {</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> hello 10;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> dead 40;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> bfd on;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> };</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> };</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> ipv4 {</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> table table1;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> export all;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> import all;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> };</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">}</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"><br></span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">protocol static static1 {</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> ipv4 {</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> table table1;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> export all;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> import all;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> };</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> route 200.1.1.1/32 via 10.100.1.11;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> route 200.1.1.2/32 via 10.100.1.11;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> route 200.1.1.3/32 via 10.100.1.11;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> route 200.1.1.4/32 via 10.100.1.11;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> route 200.1.1.5/32 via 10.100.1.11;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> route 200.1.1.6/32 via 10.100.1.11;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> route 200.1.1.7/32 via 10.100.1.11;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> route 200.1.1.8/32 via 10.100.1.11;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> route 200.1.1.9/32 via 10.100.1.11;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;"> route 200.1.1.10/32 via 10.100.1.11;</span></font></div><div><font face="JetBrainsMono-Medium"><span style="font-style: normal;">}</span></font></div></div><div><br></div><div>Regards</div><div>Prem</div><div><br></div><div></div></body></html>