DNS fix

*** Hello,

This is an Automated WATER rule intended to provide you with information, as well as gather additional information that we can use to more effectively troubleshoot your problem.

Based on the CTI and Resolver group selected, there is a problem with DNS or DHCP. Please read and provide as much detailed information that we are requesting here so that a Global IT Escalation Support Engineer can effectively resolve the issue that is being reported.

As a note, DNS can take up to 1 hour to replicate changes. If you just provisioned a new host, please allow time for the host DNS information to propagate.

1) Please provide the fully qualified domain name for the host, ex: userid.desktop.amazon.com, hostname.ant.amazon.com.

2) Please provide the current IP assigned to your host
If you are on a Unix machine (mac/Ubuntu/RHEL): ifconfig or /sbin/ifconfig
If you are on a Windows host open a command prompt and issue: "ipconfig /all"

3a) For Linux hosts, please provide the output of the "host" lookup command from your Linux box
host hostname
host ipaddress

3b) For windows hosts, please provide the output of "nslookup" for the following:
nslookup hostname
nslookup ipaddress

4) If your A record (forward) address is not pointing to the correct host, then there may be a stale A record that needs to be removed. For dev-desktops this is PROD dns, for all other laptops or workstations at CORP sites (Ubuntu, Windows, Mac) this is likely going to be ANT DNS.
For RHEL hosts, you can also lookup your hostname at https://infrastructure.amazon.com/automation/hostDetails.cgi  to see what infrastructure is feeding to desktop DNS. If this is not correct, then you may have to re-seed infrastructure with your host details: "/etc/init.d/hwinfo seed"

Please see https://w.amazon.com/index.php/Infrastructure/ServerTools/Tools/HWinfo  for more details.

5) If your PTR record (reverse) address is missing, this means it is not registered, for most corporate sites the PTR record is registered with ANT dns.

For RHEL, please try the steps outlined here: https://w.amazon.com/index.php/Linux/Desktop/DNS#Reverse_DNS
For Ubuntu, please try:  https://w.amazon.com/index.php/ClientEng/VirtualDevDesktop/FAQ#The_ant.amaz...
For Windows, please run this from a command-line: "ipconfig /release" and then "ipconfig /renew"
For all operating sytems you can also try restarting your host.

6) If you are on a RHEL or Ubuntu host, please provide the output of:
RHEL: cat /var/lib/dhclient/dhclient-eth0.leases
Ubuntu: cat /var/lib/dhcp/dhclient.leases
MAC: From a terminal window issue the command "ipconfig getpacket en0" or "ipconfig getpacket en1"
Windows, please see step 2 "ipconfig /all"

7) If you are using a RHEL host, you may be able to go to dns-manage and clear your A record (it won't work for your PTR since it's managed by ANT DNS). This sometimes can trigger your A-record to regenerate, provided that infrastructure is reflecting the correct information.

8) If you are using a Virtual RHEL host from VirtualBox, the network adapter for the virtual host should be set to "bridge mode" if it is in any other mode such as NAT. Bridge mode is the default Mode, however there have been some instances in which this has not been the case.

Why did this note get added? http://w.amazon.com/?WFA/Water  
*** Matched Water Rule: \\ DNS Issues \\ Water Rule https://cti.amazon.com/water/rule/CTI0077999