A free tool:
Category: DNS
Test DMARC record for a domain
article #1086, updated 2688 days ago
SPF for Constant Contact
article #873, updated 2696 days ago
Awhile ago it came to light that the following needed to be added to SPF records for email-enabled domains using Constant Contact:
include:ccsend.com include:constantcontact.com include:confirmedcc.com
Things have gotten a lot better. The following now covers all of the above:
ip4:208.75.120.0/22
DNS Root Servers
article #1017, updated 2925 days ago
As of this writing, the current authoritative list, from here:
https://www.iana.org/domains/root/servers
is:
| a.root-servers.net | 198.41.0.4 | 2001:503:ba3e::2:30 | VeriSign, Inc. |
| b.root-servers.net | 192.228.79.201 | 2001:500:84::b | University of Southern California (ISI) |
| c.root-servers.net | 192.33.4.12 | 2001:500:2::c | Cogent Communications |
| d.root-servers.net | 199.7.91.13 | 2001:500:2d::d | University of Maryland |
| e.root-servers.net | 192.203.230.10 | 2001:500:a8::e | NASA (Ames Research Center) |
| f.root-servers.net | 192.5.5.241 | 2001:500:2f::f | Internet Systems Consortium, Inc. |
| g.root-servers.net | 192.112.36.4 | 2001:500:12::d0d | US Department of Defense (NIC) |
| h.root-servers.net | 198.97.190.53 | 2001:500:1::53 | US Army (Research Lab) |
| i.root-servers.net | 192.36.148.17 | 2001:7fe::53 | Netnod |
| j.root-servers.net | 192.58.128.30 | 2001:503:c27::2:30 | VeriSign, Inc. |
| k.root-servers.net | 193.0.14.129 | 2001:7fd::1 | RIPE NCC |
| l.root-servers.net | 199.7.83.42 | 2001:500:9f::42 | ICANN |
| m.root-servers.net | 202.12.27.33 | 2001:dc3::35 | WIDE Project |
Installing nslookup on Linux
article #1008, updated 2986 days ago
Increasingly, nslookup is not installed by default in major Linux distros. On Arch-based and Debian-based distros, it’s in package dnsutils,
Opt out of the Cox special DNS
article #884, updated 3361 days ago
By default, Cox will DHCP to your systems some DNS servers which behave like OpenDNS, i.e., if there is a DNS name miss, the servers will show a hit which is a Cox search page. This can confuse a lot of things. Cox has provided a way around this:
for residential at least, it uses these two IPs as static DNS:
68.105.28.13 68.105.29.13
and these do appear to be noticeably faster!
CenturyLink DNS servers
article #881, updated 3364 days ago
A great place to find them:
http://internethelp.centurylink.com/internethelp/dns-ctl.html
DNS Root Server IPs
article #780, updated 3640 days ago
Here is the canonical source:
'dig' command to pull up all records for a single hostname
article #597, updated 4139 days ago
To pull up a list of all DNS records for a single hostname:
dig +nocmd yourdomain.com any +multiline +noall +answer
Web/GUI front ends for BIND
article #287, updated 5018 days ago
Here is an interesting list:
http://www.debianadmin.com/bind-dns-server-web-interfacefrontend-or-gui-tools.html
But the best may be here:
SPF records for email
article #228, updated 5179 days ago
SPF records are DNS entries for entire domains, which do a whole lot to prevent spam. They are required on the sender side, these days, for email to be successfully received by many carriers small and large, including Yahoo and Embarq and many others. For lots of general information:
For more details and syntax: