Red Hat Bugzilla – Bug 1180267
root key management does not comply with RFC5011
Last modified: 2015-12-07 07:30:36 EST
Description of problem: unbound-anchor is not run in the right interval so our unbound package does not comply with RFC 5011: http://tools.ietf.org/html/rfc5011#section-2.3 says: A resolver that has been configured for an automatic update of keys from a particular trust point MUST query that trust point (e.g., do a lookup for the DNSKEY RRSet and related RRSIG records) no less often than the lesser of 15 days, half the original TTL for the DNSKEY RRSet, or half the RRSIG expiration interval and no more often than once per hour. The expiration interval is the amount of time from when the RRSIG was last retrieved until the expiration time in the RRSIG. That is, queryInterval = MAX(1 hr, MIN (15 days, 1/2*OrigTTL, 1/2*RRSigExpirationInterval)) Current DNSKEY TTL in root zone is 172800 seconds, i.e. 172800/60/60/24 = 2 days. It means that unboud-anchor should be run at least once a day. Currently, unbound-anchor is run once a month instead of once a day. Version-Release number of selected component (if applicable): unbound-1.4.20-19.el7 How reproducible: 100 % Steps to Reproduce: 1. look at /etc/cron.d/unbound-anchor Actual results: Currently, unbound-anchor is run once a month instead of once a day. Expected results: Current DNSKEY TTL in root zone is 172800 seconds, i.e. 172800/60/60/24 = 2 days. It means that unboud-anchor should be run at least once a day. Additional info: It might be better to convert cron job to systemd timer so it could get run once a day at random time. Currently it gets run at the very same time on all RHEL machines with the package. That could lead to spikes in network traffic ...
Thank you for noticing this.
From engineering point of view, this bug can not be properly verified without Bug #1215645 being fixed first. The Bug #1215645 is hard blocker for this issue and if Bug #1215645 will not be fixed in 7.2, then this bug can not be releases as part of Unbound update.
with fix in redhat-release (server/client) the unbound-anchor.timer is set even after reboot of system # systemctl status unbound-anchor.timer unbound-anchor.timer - daily update of the root trust anchor for DNSSEC Loaded: loaded (/usr/lib/systemd/system/unbound-anchor.timer; enabled) Active: active (waiting) since Fri 2015-09-25 11:29:21 EDT; 3min 40s ago Docs: man:unbound-anchor(8) Sep 25 11:29:21 kvm-guest-03.rhts.eng.bos.redhat.com systemd[1]: Starting daily update of the root trust anchor ...EC. Sep 25 11:29:21 kvm-guest-03.rhts.eng.bos.redhat.com systemd[1]: Started daily update of the root trust anchor f...EC.
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://rhn.redhat.com/errata/RHSA-2015-2455.html