AD intrasite replication slow

Question

Curious to understand why our DNS AD replication seems slower intrasite than intersite. We have not modified any of the reg settings re: replication but have turned on change notification between sites for all sites and set the minimum 15 minutes. The following stats are blocks where the first record is the DC where the DNS record is created and the subsequent timestamps show when the record appeared on the other DCs. What is strange that intrasite replication seems slower than intersite? Why would intrasite replication take a minute or more in most cases?

e.g. in the first block it took over two minutes for the record to reach another DC in the same site but it got to 3 other DCS in other sites first???

SITE-E520 09:02:32
SITE-F530 09:03:00
SITE-F531 09:03:36
SITE-G531 09:04:03
SITE-E531 09:04:46
SITE-F520 09:04:58
SITE-E530 09:05:02
                  
SITE-F520 09:05:03
SITE-E520 09:05:24
SITE-F530 09:06:01
SITE-F531 09:06:37
SITE-G531 09:07:04
SITE-E531 09:07:46
SITE-E530 09:08:03
                  
SITE-E531 09:08:03
SITE-E520 09:08:25
SITE-F530 09:09:01
SITE-F531 09:09:37
SITE-G531 09:10:05
SITE-F520 09:10:59
SITE-E530 09:11:03
                  
SITE-F531 09:11:04
SITE-E520 09:11:25
SITE-F530 09:12:02
SITE-G531 09:13:06
SITE-E531 09:13:47
SITE-F520 09:13:59
SITE-E530 09:14:03
                  
SITE-F530 09:14:04
SITE-F531 09:15:38
SITE-G531 09:16:06
SITE-E531 09:16:47
SITE-F520 09:17:00
SITE-E530 09:17:04
SITE-E520 09:17:25
                  
SITE-E530 09:17:26
SITE-F530 09:18:02
SITE-F531 09:18:38
SITE-G531 09:19:07
SITE-E531 09:19:48
SITE-F520 09:20:00
SITE-E520 09:20:26
                  
SITE-G531 09:20:26
SITE-F530 09:21:02
SITE-F531 09:21:39
SITE-E531 09:22:48
SITE-F520 09:23:00
SITE-E530 09:23:04
SITE-E520 09:23:26

Answer 1

Might check to see things look Ok here.

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