'RRset exists (value dependent)' DNS logs

[ZaNaToS]

I see this many times everyday in my /var/log/messages file :

Oct 19 08:38:32 web named[815]: client 83.171.213.25#17969: update 'domain.tld/IN' denied
Oct 19 09:38:29 web named[815]: client 83.171.213.25#18011: updating zone 'domain.tld/IN': update failed: 'RRset exists (value dependent)' prereq
uisite not satisfied (NXRRSET)

any one has a clue what this is ?

 

[rvdmeer]

A set of RRs with a specified NAME and TYPE exists and has the same members with the same RDATAs as the RRset specified here in this section. While RRset ordering is undefined and therefore not significant to this comparison, the sets be identical in their extent.

For this prerequisite, a requestor adds to the section an entire RRset whose preexistence is required. NAME and TYPE are that of the RRset being denoted. CLASS is that of the zone. TTL must be specified as zero (0) and is ignored when comparing RRsets for identity.

 

[jamesyeeoc]

The simpler answer is that since it was an incoming (/IN) DNS update, if you do not have another DNS server of yours which is supposed to update this server's DNS for that domain, then it is just someone trying to poison your DNS.

If this is the case,then block that 83.xx.xx.xx IP address at your firewall. It appears to be a DSL customer:

Answer:
83.171.213.25 PTR record: dslcustomer-213-25.vivodi.gr. [TTL 10800s] [A=83.171.213.25]

 

[ZaNaToS]

I have to admit that it was very difficult for me to understand the explanation rvdmeer ...but james got everything clear to me.

thank you guys.