[Solved] url_helper.py[WARNING]: Calling 'http://169.254.169.254/2009-04-04/meta-data/instance-id' failed [75/120s]: unexpected error ['NoneType' object has no attribute 'status_code']

Issue:- I was enabling the ENA support for the centos7.1 on the ec2 instance when i received following error
url_helper.py[WARNING]: Calling 'http://169.254.169.254/2009-04-04/meta-data/instance-id' failed [75/120s]: unexpected error ['NoneType' object has no attribute 'status_code']

Due to which mynetwork card was not coming up for the instance and it was further resulting the instance-id failure due to which url_helper.py script of the AWS was failing to get the ip address. So when finally instance was booted as no ip was assigned to it the ssh checks known as instance checks were failing on the instance.

I was getting following logs which confirmed it

Cloud-init v. 0.7.5 running 'init' at Mon, 04 Mar 2018 06:33:38 +0000. Up 5.17 seconds.
cis-info: +++++++++++++++++++++++Net device info++++++++++++++++++++++++
cis-info: +--------+-------+-----------+-----------+-------------------+
cis-info: | Device |   Up  |  Address  |    Mask   |     Hw-Address    |
cis-info: +--------+-------+-----------+-----------+-------------------+
cis-info: | ens5:  | False |     .     |     .     | 06:f7:b8:fc:f1:20 |
cis-info: |  lo:   |  True | 127.0.0.1 | 255.0.0.0 |         .         |
cis-info: +--------+-------+-----------+-----------+-------------------+
cis-info: ++++++++++++++++++++++++++Route info+++++++++++++++++++++++++++
cis-info: +-------+-------------+---------+---------+-----------+-------+
cis-info: | Route | Destination | Gateway | Genmask | Interface | Flags |
cis-info: +-------+-------------+---------+---------+-----------+-------+
cis-info: +-------+-------------+---------+---------+-----------+-------+
2018-03-03 22:33:38,836 - url_helper.py[WARNING]: Calling 'http://169.254.169.254/2009-04-04/meta-data/instance-id' failed [0/120s]: unexpected error ['NoneType' object has no attribute 'status_code']


Cause:-
In the AWS Documentation it is mentioned to add GRUB_CMDLINE_LINUX=”net.ifnames=0” in the /boot/grub2/grub.cfg but for me.

Solution:-
I changed it and updated in the /etc/default/grub and recreated the grub.

After which the problem was resolved and I was successfully able to upgrade the instance to 5th generation support.

After the change i got the following output in the logs

Cloud-init v. 0.7.5 running 'init' at Mon, 04 Mar 2018 07:43:28 +0000. Up 8.73 seconds.
cis-info: ++++++++++++++++++++++++++Net device info++++++++++++++++++++++++++
cis-info: +--------+------+-------------+---------------+-------------------+
cis-info: | Device |  Up  |   Address   |      Mask     |     Hw-Address    |
cis-info: +--------+------+-------------+---------------+-------------------+
cis-info: | ens5:  | True | 10.98.16.98 | 255.255.255.0 | 06:f7:b8:fc:f1:20 |
cis-info: |  lo:   | True |  127.0.0.1  |   255.0.0.0   |         .         |
cis-info: +--------+------+-------------+---------------+-------------------+
cis-info: +++++++++++++++++++++++++++++++Route info+++++++++++++++++++++++++++++++
cis-info: +-------+-------------+------------+---------------+-----------+-------+
cis-info: | Route | Destination |  Gateway   |    Genmask    | Interface | Flags |
cis-info: +-------+-------------+------------+---------------+-----------+-------+
cis-info: |   0   |   0.0.0.0   | 10.98.16.1 |    0.0.0.0    |    ens5   |   UG  |
cis-info: |   1   |  10.98.16.0 |  0.0.0.0   | 255.255.255.0 |    ens5   |   U   |
cis-info: +-------+-------------+------------+---------------+-----------+-------+
Cloud-init v. 0.7.5 running 'modules:config' at Mon, 04 Mar 2018 07:43:30 +0000. Up 10.16 seconds.