/etc/cron.d/rule-update should avoid overwhelming rule sites

[dougburks]

sleep a random number of seconds/minutes to avoid overwhelming rule sites

[dougburks]

https://groups.google.com/d/topic/security-onion-testing/pkefnDcBEbQ/discussion

[dougburks]

if master, then sleep for up to 50 minutes:
RMIN=$(($(dd if=/dev/urandom count=1 2> /dev/null | cksum | cut -d' ' -f1) % 50));

if sensor, then sleep for 60 minutes to give master time to download rules

[dougburks]

commit:
Security-Onion-Solutions/securityonion-rule-update@8038355

[dougburks]

submitted for testing:
https://groups.google.com/d/topic/security-onion-testing/k_1lsxKBk3s/discussion

[dougburks]

Published:
http://blog.securityonion.net/2015/08/new-rule-update-and-setup-packages.html