IMO, what PLDT should have done is to use OpenDNS resolvers as "parents" of their own in-house DNS servers. Maybe at the same time, the original user who had set custom OpenDNS settings did not yet update his/her IP at OpenDNS, I don't know. My client was clearly using NGN Dynamic IP, and therefore, when she gets an IP which was probably previously assigned to another user who has set his/her own custom OpenDNS filters, my client gets the net effect of having the same filters applied to her network via the IP address. I think their network admins assumed that no one among their customers are using custom OpenDNS content filtering settings *on their Dynamic IPs!*. They should not have configured the OpenDNS resolver to be passed directly to their customers. However good, the implementation is very poor, IMO, in relation to PLDTs own network. So now, it appears that PLDT is using OpenDNS on their network, which is a good step in the right direction. Testing with the NSLOOKUP command resulted in a failing primary DNS resolver (typical PLDT) which naturally passed the DNS request to the secondary resolver (OpenDNS). Upon verifying with the owner, she was not using OpenDNS (not even aware of it) so I ran a quick IPCONFIG /ALL and found out this: I immediately proceeded to try and reproduce the selective browsing problem, then lo and behold, I loaded Yahoo Mail, and immediately got the OpenDNS landing page for blocked or filtered sites! What!? Problem was, selective browsing and intermittent connection according to the owner. I was called to service a client using PLDT DSL 3Mbps connection. That is often used by new internet contracts.Just wanted to share an observation from my troubleshooting sortie yesterday. The reason I could imagine for those two IPs is that your router caches DNS requests and returns an old IP.Īnother problem could be DualStack Lite. To specify an IP version, use dig -4 or dig -6 as shown in Mafketel's answer. This will return your IP address, version 4 or 6, depending on dig's connection. Thus, a more robust command might be: dig +short ANY If dig establishes a connection to via IPv6, you'll get no result back (since you asked for your IPv4 address but have an IPv6 address in use). Note that per default, dig asks for the IPv4 address ( DNS A record). The reasons why the method of querying the WAN IP using DNS is better were mentioned by krinkle: standardised, more stable and faster. This server is programmed that, if this special domain is requested, the IP the request comes from is sent back. The command you mentioned is: dig +short this command does is: it sends a request for the IP of the domain to the DNS server. dig would request the IP assigned to the domain. Does it mean, that ip1 is no proper "internet IP" but more like a LAN IP?įirst to summarize the general usage of dig: it requests the IP assigned to the given domain from the default DNS server. But, again, what is doing then?Īdditionally: Opening ip1 from within my LAN is giving me the test website from my RasPi, opening it from the outside of my LAN (mobile internet) does not work. I could imagine that my ISP is using some kind of sub-LAN, so that my requests to webservers are going through another (ISP-) router which has ip2, so that is just seeing this address (ip2). There has to be a difference, because the WAN-IP I get from dig +short (ip1) is the one I can also see in the web interface of my router, whereas (and other similar sites too) is giving me another IP address (ip2). Why is it better and what is the difference? That this "dns-approach" would be better than the "http-approach". In the answer of Krinkle on the question I mentioned, it is stated How does it do it? Where does it get my IP from? And how is it different to what webpages, like e.g., are doing? They also try to get my IP. So is just emulating a domain, which is resolved to my router? If I would write instead, I would get the IP address of the domain right? Which is asked what IP address belongs to the given domain Here is what I (hope to) understand so far (please correct me, if I am wrong): I found this question and, among others, a solution with dig was proposed: dig +short works perfectly, but now I want to understand what it is doing. I needed to automatically get my own WAN-IP-address from my router.
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