Cloud-init delay - sometimes

[Dick Visser <dick.visser@geant.org>]

Hi

I'm regularly reinstantiating many AWS instances that run Debian  (bullseye).
I see some strange behavior, in that instance come up very
consistently in about 6 seconds (according to
/var/log/cloud-init-output.log).
But every now and then it takes much longer, in the order of 40 seconds.

Sample sequence of newly created instances (head -1
/var/log/cloud-init-output.log):

Cloud-init v. 20.4.1 running 'init-local' at Tue, 28 Sep 2021 15:07:27
+0000. Up 5.52 seconds.
Cloud-init v. 20.4.1 running 'init-local' at Tue, 28 Sep 2021 15:12:58
+0000. Up 4.75 seconds.
Cloud-init v. 20.4.1 running 'init-local' at Tue, 28 Sep 2021 15:18:36
+0000. Up 4.87 seconds.
Cloud-init v. 20.4.1 running 'init-local' at Tue, 28 Sep 2021 16:03:54
+0000. Up 5.42 seconds.
Cloud-init v. 20.4.1 running 'init-local' at Tue, 28 Sep 2021 16:05:49
+0000. Up 4.96 seconds.
Cloud-init v. 20.4.1 running 'init-local' at Tue, 28 Sep 2021 16:07:38
+0000. Up 5.77 seconds.
Cloud-init v. 20.4.1 running 'init-local' at Tue, 28 Sep 2021 16:09:30
+0000. Up 6.20 seconds.
Cloud-init v. 20.4.1 running 'init-local' at Tue, 28 Sep 2021 16:11:25
+0000. Up 5.64 seconds.
Cloud-init v. 20.4.1 running 'init-local' at Tue, 28 Sep 2021 16:13:50
+0000. Up 42.21 seconds.

I guess this is not a problem with the Debian image, and I can
probably configure our deployment to cope with this delay, but I'm
curious as to why this happens.
FYI this is an eu-central-1 (frankfurt).

thx

-- 
Dick Visser
Trust & Identity Service Operations Manager
GÉANT