DNS checking website

https://www.whatsmydns.net/

useful for checking if 3rd party has created the txt record or not when setting up SSL certs with godaddy.

the txt record needs to be created on the main .domain.com not subdomain.domain.com

Use nslookup to find the IP addresses of the domain controllers

You can use Nslookup is a command-line tool that displays information you can use to diagnose Domain Name System (DNS) infrastructure.

1. Click Start, and then click Run.
2. In the Open box, type cmd.
3. Type nslookup, and then press ENTER.
4. Type set type=all, and then press ENTER.
5. Type _ldap._tcp.dc._msdcs.

cheatsheet making site

http://www.cheatography.com/

simple ftp program for windows

http://smallftpd.sourceforge.net/

testing bandwidth

iperf
https://iperf.fr/

good for testing across WAN links etc


Server
iperf -s

Client (run test for 30 seconds)
iperf -c x.x.x.x -R -t 30


Iperf3 is the latest version (set the bandwidth to get the full speed)

iperf3.exe -u -c x.x.x.x -b 1000M -t 30

-i creates more streams

-u can give better performance also

Window size can give better results too.

iperf3.exe -u -c x.x.x.x -b 1000M -t 60 -w 64MB -i 3

multiping tool

http://www.nessoft.com/multiping/

screenshot software

http://getgreenshot.org/

subnet calculator tool

Good calculator here for dividing up larger subnets into smaller ones
http://www.davidc.net/sites/default/subnets/subnets.html

A /16 breaks up into two /17's, a /17 breaks up into two /18's and so on

As you break up a /16 you get more networks but less hosts

mask	networks	hosts
/16	1	65534
/17	2	32766
/18	4	16382
/19	8	8190
/20	16	4096
/21	32	2046
/22	64	1022
/23	128	510
/24	256	254
/25	512	126
/26	1024	62
/27	2048	30
/28	4096	14
/29	8192	6
/30	16384	2