We have weird situation, we have configured mod_evasive with apache 2.4 on Ubuntu 14. we have added google bot IPs in white list(we are maintaining long list of internal and external IPs in white list). But google IPs are still blocked by mod_evasive.
We have checked mod_evasive functionality, it is working fine(we have tested with Apache benchmark tool by adding IP in whitelist). Following is configuration, Originally IP-66.249.66.5 is part of subnet 66.249.64.0/19, but we have added it with 24 and 32 subnet
<ifmodule mod_evasive20.c>
DOSHashTableSize 3097
DOSPageCount 8
DOSSiteCount 50
DOSPageInterval 1
DOSSiteInterval 3
DOSBlockingPeriod 600
DOSLogDir /var/log/mod_evasive
DOSEmailNotify abc@abc.com
DOSWhitelist 66.249.66.5 66.249.0.0/16 66.249.64.0/19
</ifmodule>
root@ip-10:~# apachectl -M | grep -i ev
evasive20_module (shared)
Based on https://www.linode.com/docs/websites/apache-tips-and-tricks/modevasive-on-apache you should be using wildcards and not subnetting. For example something like the following (which is not exactly what you had with subnetting):
DOSWhitelist 66.249.*.*