dns
what is the multicast doing on 224.0.0.251? [closed]
Those look much like Bonjour / mDNS requests to me. Those packets use multicast IP address 224.0.0.251 and port 5353. The most likely source for this is Apple iTunes, which comes pre-installed on Mac computers (and is a popular install on Windows machines as well). Apple iTunes uses it to discover other iTunes-compatible devices in … Read more
Load balancer and API Gateway confusion
API Gateway and Load Balancer are 2 different things. Load Balancer -> Its a software which works at protocol or socket level (eg. tcp, http, or port 3306 etc.) Its job is to balance the incoming traffic by distributing it to the destinations with various logics (eg. Round robin). I doesn’t offer features such as … Read more
xn-- on domain, what it means?
Its the result of IDNA encoding; i.e. converting your unicode domain name to its ASCII equivalent which has to be done as DNS is not unicode-aware. The xn-- says “everything that follows is encoded-unicode”.
What does the authority section mean in dig results? [closed]
The Authority section indicates the server(s) that are the ultimate authority for answering DNS queries about that domain. The reason for this section is that you can query any* DNS server(s) to answer a query for you. That server may choose though to answer the query from a cache. However, if you want to ensure … Read more
How does domain registration work? [closed]
Registrars job is primarily to coordinate and make sure there are no duplicates in domain names. ICANN manages them. At a technical level registrars (and registries) use the Extensible Provisioning Protocol to achieve this. They do update the DNS with nameserver information but not the Root DNS servers (which is an entirely different area) only … Read more
How to simulate browsing from various locations?
This is a bit of self promotion, but I built a tool to do just this that you might find useful, called GeoPeeker. It remotely accesses a site from servers spread around the world, renders the page with webkit and sends back an image. It will also report the IP address and DNS information of … Read more
What is the maximum length of a DNS name
With your way of counting, the domain name a.b.c.d.e. would be considered to be five characters long. It suspect that not many people will find that way of counting useful. That way of counting also makes the maximum length vary with the number of labels, so when you have four labels the maximum length is … Read more
How do I set up GitHub Pages to redirect DNS requests from a subdomain (e.g. www) to the top-level domain (TLD, Apex record)?
Short answer Step 1: Add a new file CNAME to your GitHub Pages repository containing only one line: your top-level domain name. E.g.: example.com Step 2: [Optional] but highly recommended 2.1: Remove all other top-level records (prefixed with @) of type A from your DNS configuration. 2.2: Remove a CNAME record for the second-level domain … Read more
Domain IP address for www and non-www for Canonical URL
The mechanisms you describe (A and CNAME records vs. 301 redirects) are part of two different protocols (DNS and HTTP). A and CNAME records have nothing to do with which site your HTTP server serves for different requests. Let’s look at two different DNS configurations: Configuration 1 (CNAME record) Host | Type | Data —————–+——-+————- … Read more