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Re: More sorbs blacklisting



Pigeon wrote:
...this kind of brings me back to what I guess was a point somewhat
obscured by my rambling... How does one retrieve the *definitive*
information as to whether an IP is static or dynamic?

Well, there are a number of criteria. How the IP is assigned to your system when you start that network interface is one way. However, it's quickly becoming somewhat irrelevant - *many* static-IP services are just set up with a one-to-one mapping of login usernames or MAC addresses to IP addresses, and the IP is picked up via PPP(oE) or DHCP. (Or PPPoA which seems to be used in the UK.)

An ISP wanting to keep customers happy should, IMO, keep the real static-IP customers (whether those with real subnets of their own, or "just" PPP/DHCP-assigned statics) separate from the unwashed residential masses - ie, those who have no guarantee of any kind whether they'll get the same IP if they connect and disconnect several times in a row.

As I posted, my ISP said personally to me that my IP is in a block
which is "technically" dynamic.

Which implies that you're getting an IP via PPP or DHCP, and there is less formalism than might be ideal in how that IP assignment happens.

Can your ISP provide "real" rDNS instead of the username.adsl.whatever you posted near the beginning of the thread? (IE, if you have a domain name, will your ISP put yourhost.yourdomain as the rDNS for "your" IP?)

If not....  that's not helpful to your cause.

**The trouble is that "whois 213.162.113.17" doesn't give any
information either way, so where is the definitive information held?**

If WHOIS is ambiguous, other critera must be used. Such as, oh, say, rDNS. And unfortunately rDNS containing ".adsl." or ".dsl." is often considered "dynamic" IP space. See my IMO above, and add to that that IMO such an ISP should also indicate clearly in the rDNS that the IP is static.

How do I get an unbiased and definitive answer as to whether it is
"really" dynamic or static?

In your case.... I don't think you can, unless you can convince your ISP to clarify one or both of the WHOIS data for the netblock (213.162.112/19 for the IP you quote above) and the rDNS, which comes back completely empty for me:

kdeugau@olddns:~$ dig 18.113.162.213.in-addr.arpa +trace

; <<>> DiG 9.2.4 <<>> 18.113.162.213.in-addr.arpa +trace
;; global options:  printcmd
[snip root servers]

113.162.213.in-addr.arpa. 172800 IN     NS      ns0.parbin.co.uk.
113.162.213.in-addr.arpa. 172800 IN     NS      ns1.parbin.co.uk.
;; Received 93 bytes from 202.12.29.59#53(SEC1.APNIC.NET) in 337 ms

113.162.213.in-addr.arpa. 21600 IN SOA ns0.parbin.co.uk. hostmaster.parbin.co.uk. 1148395558 10800 3600 604800 21600
;; Received 108 bytes from 213.162.97.129#53(ns0.parbin.co.uk) in 106 ms

kdeugau@olddns:~$


Good luck. Look at it this way: It's *much* easier to get off of one large central blacklist like SORBS than it is to get out of millions of local mail admins' local blacklist databases.

-kgd



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