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<p>Hello, all<br>
</p>
I got a weird question. We recently migrated two our routers from
CentOS 7 to Debian 10, installed Bird, placed config files back -
and since then we are observing BGP flaps.</div>
<div><br>
</div>
<div>Moreover, flaps are observed on IPv6 peers only:</div>
<div><br>
</div>
<div><font face="monospace">Name Proto Table State
Since Info<br>
device1 Device --- up 2021-03-18 15:42:27 <br>
direct1 Direct --- up 2021-03-18 15:42:27 <br>
kernel1 Kernel master4 up 2021-03-18 15:42:27 <br>
kernel2 Kernel master6 up 2021-03-18 15:42:27 <br>
static1 Static master4 up 2021-03-18 15:42:27 <br>
static2 Static master6 up 2021-03-18 15:42:27 <br>
UPLINK BGP --- up 2021-03-18 15:42:31
Established <br>
UPLINKv6 BGP --- up 2021-03-22 21:11:12
Established <br>
AR1 BGP --- up 2021-03-18 15:42:31
Established <br>
AR1v6 BGP --- up 2021-03-19 23:42:55
Established <br>
AR2 BGP --- up 2021-03-18 15:42:28
Established <br>
AR2v6 BGP --- up 2021-03-20 15:37:38
Established <br>
BR2 BGP --- up 2021-03-18 15:42:28
Established <br>
BR2v6 BGP --- up 2021-03-21 11:03:33
Established <br>
ospf4 OSPF master4 up 2021-03-18 15:42:27
Running<br>
ospf6 OSPF master6 up 2021-03-18 15:42:27
Running</font><br>
</div>
<div><br>
</div>
<div>Flaps are unregular, currently we saw no coincedences with
anything. The network is stable, our and peers configs were not
changed, Bird version too (2.0.7 on both CentOS and Debian).</div>
<div><br>
</div>
<div>The only message about this in logs is hold-related:</div>
<div><br>
</div>
<div>2021-03-22 21:01:10 <WARN> Kernel dropped some netlink
messages, will resync on next scan.<br>
2021-03-22 21:04:33 <WARN> Kernel dropped some netlink
messages, will resync on next scan.<br>
2021-03-22 21:06:10 <WARN> Kernel dropped some netlink
messages, will resync on next scan.<br>
2021-03-22 21:10:12 <RMT> UPLINKv6: Error: Hold timer
expired<br>
2021-03-22 21:10:13 <WARN> Kernel dropped some netlink
messages, will resync on next scan.<br>
2021-03-22 21:10:15 <WARN> Kernel dropped some netlink
messages, will resync on next scan.<br>
2021-03-22 21:10:16 <WARN> Kernel dropped some netlink
messages, will resync on next scan.<br>
2021-03-22 21:10:16 <WARN> Kernel dropped some netlink
messages, will resync on next scan.<br>
<br>
</div>
<div>Could you please suggest some way to go except of returning to
CentOS? <br>
</div>
<div><br>
</div>
<div>Thank you in advance.<br>
</div>
<div><br>
<font color="grey"><sub>--<br>
<div class="moz-signature"></div>
</sub></font></div>
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