How to check any firewalls rules for Virtual network and VM

Question

How to check any firewalls rules for Virtual network and VM

sns 9,246

How to check any firewalls rules for Virtual network?

I have tried to install crowd strike on one linux VM from one subscription it worked ( this is differet virtual network)

I have tried to install same package of crowd strike from another VM for other subscription. It failed with below error. what could be the issue? and how to check whether any firewall blockage ? ( this is different virtual network and different subscirption

I heared it is associated with HUb network where it has got firewalls.

But what are all need to check. Please suggest

Error:

Michael Durkan 12,241 Reputation points MVP

2023-12-15T21:05:31.2566667+00:00
Hi

try using the IP Flow Verify feature in Azure Network Watcher:

https://learn.microsoft.com/en-us/azure/network-watcher/ip-flow-verify-overview

Hope this helps,

Thanks

Michael Durkan

If the reply was helpful please upvote and/or accept as answer as this helps others in the community with similar questions. Thanks!
sns 9,246 Reputation points

2023-12-16T10:00:05.0566667+00:00

Hi Michael,

In my case what details I should provide? for packet details
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-19T05:58:05.2+00:00
@sns

Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.

I understand that you are unable to install a package on a Linux VM and would like to know if Azure platform might be blocking the connection.

From the error message, it appears connection time out is issued for the site,

"https://rhui4-1.microsoft.com/pulp/repos/content/dist/rhel9/rhui/9/x86_"

What you can do is,

1.

Do a dns lookup from the affected VM and get the IP of the service.

See :

Use the IP which your VM resolves to and check the IP Flow Verify

Direction : Outbound, Local Port : 1234
Remote IP : <IPfromDnsLookUp>, Remote Port : 443

Run using the above parameters and check if there is any NSG or UDR blocking.

2.Try to do a telnet or curl to the FQDN.

Open terminal/shell

Run

curl https://rhui4-1.microsoft.com

See if the above succeeds or gives any error.

Cheers,

Kapil
sns 9,246 Reputation points

2023-12-19T06:25:59.0433333+00:00

HI Kapil,

I see as following
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-19T06:49:25.6533333+00:00
@sns

It appears your VM does not have connectivity to any other server at all.

Please run,

nslookup https://rhui4-1.microsoft.com 8.8.8.8

nslookup https://rhui4-1.microsoft.com 168.63.129.16

curl https://www.google.com

and share the results

Cheers,

Kapil
sns 9,246 Reputation points

2023-12-19T07:07:22.72+00:00

HI Kapil,

Here are the results:
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-19T09:30:21.0166667+00:00
@sns

I am sorry, we should not use https while doing nslookup.

Please run,

nslookup rhui4-1.microsoft.com 8.8.8.8

nslookup rhui4-1.microsoft.com 168.63.129.16

nslookup www.google.com 8.8.8.8

nslookup www.google.com 168.63.129.16

curl https://8.8.8.8

ifconfig

and share the results

With curl https://www.google.com, looks like your Linux VM does not have a DNS server.

The name resolution fails irrespective of the end point.

Cheers,

Kapil
sns 9,246 Reputation points

2023-12-19T09:38:04.8766667+00:00

HI Kapil,

Here are the results:

and

and
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-19T12:35:49.29+00:00
@sns

It looks like your VM does not have a DNS server configured at all.

If this is a Dev/Test environment, I would suggest you to to deploy a new VM altogether.

If you are interested in troubleshooting this VM,

1.First your VM must have a proper DNS configuration.

Ideally, this is how a DNS lookup output should appear for a Linux Distros

The 127.0.0.53 IP used here refers to a service running locally on your linux VM taking care of DNS.

Since you are not getting a DNS server, you should manually add a DNS server.

Run sudo vi /etc/resolv.conf

Add a line nameserver 168.63.129.16 after the comments.

Save and close the file

Now DNS resolution will use Azure Wireserver IP and would look like below

2.Once DNS issue is resolved, we can check the connectivity issue.

Please share the results of creating a new VM or DNS troubleshooting of this VM.

nslookup www.google.com

Cheers,

Kapil
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-21T10:08:54.8833333+00:00

@sns

Reaching out to check if there are any questions on this.

Please let us know if we can be of any further assistance here.

Thanks,

Kapil
sns 9,246 Reputation points

2023-12-21T10:18:27.7966667+00:00

HI Kapil,

it is working now. You can close case. Thank you
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-21T10:27:48.02+00:00

@sns

You are most welcome.

I have summarized my comments and posted it as a new answer.

I would highly appreciate if you could Accept the answer and close this thread

Original posters help the community find answers faster by identifying the correct answer.

Thanks,

Kapil
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-22T12:05:28.28+00:00

@sns

Just checking in to see if the below answer helped. If this answers your query, please don’t forget to click "Accept the answer" and Up-Vote for the same, which might be beneficial to other community members reading this thread. And, if you have any further query do let us know.

Thanks,

Kapil
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-26T07:47:47.5266667+00:00

@sns

Reaching out to check if there are any questions on this.

Please let us know if we can be of any further assistance here.

Thanks,

Kapil

Please Accept an answer if correct.

Original posters help the community find answers faster by identifying the correct answer.

1 answer

Your answer

Michael Durkan 12,241 Reputation points MVP

2023-12-15T21:05:31.2566667+00:00

Hi

try using the IP Flow Verify feature in Azure Network Watcher:

https://learn.microsoft.com/en-us/azure/network-watcher/ip-flow-verify-overview

Hope this helps,

Thanks

Michael Durkan

If the reply was helpful please upvote and/or accept as answer as this helps others in the community with similar questions. Thanks!
sns 9,246 Reputation points

2023-12-16T10:00:05.0566667+00:00

Hi Michael,

In my case what details I should provide? for packet details
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-19T05:58:05.2+00:00

@sns

Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.

I understand that you are unable to install a package on a Linux VM and would like to know if Azure platform might be blocking the connection.

From the error message, it appears connection time out is issued for the site,

"https://rhui4-1.microsoft.com/pulp/repos/content/dist/rhel9/rhui/9/x86_"

What you can do is,

1.

Do a dns lookup from the affected VM and get the IP of the service.

See :

Use the IP which your VM resolves to and check the IP Flow Verify

Direction : Outbound, Local Port : 1234
Remote IP : <IPfromDnsLookUp>, Remote Port : 443

Run using the above parameters and check if there is any NSG or UDR blocking.

2.Try to do a telnet or curl to the FQDN.

Open terminal/shell

Run

curl https://rhui4-1.microsoft.com

See if the above succeeds or gives any error.

Cheers,

Kapil
sns 9,246 Reputation points

2023-12-19T06:25:59.0433333+00:00

HI Kapil,

I see as following
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-19T06:49:25.6533333+00:00

@sns

It appears your VM does not have connectivity to any other server at all.

Please run,

nslookup https://rhui4-1.microsoft.com 8.8.8.8

nslookup https://rhui4-1.microsoft.com 168.63.129.16

curl https://www.google.com

and share the results

Cheers,

Kapil
sns 9,246 Reputation points

2023-12-19T07:07:22.72+00:00

HI Kapil,

Here are the results:
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-19T09:30:21.0166667+00:00

@sns

I am sorry, we should not use https while doing nslookup.

Please run,

nslookup rhui4-1.microsoft.com 8.8.8.8

nslookup rhui4-1.microsoft.com 168.63.129.16

nslookup www.google.com 8.8.8.8

nslookup www.google.com 168.63.129.16

curl https://8.8.8.8

ifconfig

and share the results

With curl https://www.google.com, looks like your Linux VM does not have a DNS server.

The name resolution fails irrespective of the end point.

Cheers,

Kapil
sns 9,246 Reputation points

2023-12-19T09:38:04.8766667+00:00

HI Kapil,

Here are the results:

and

and
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-19T12:35:49.29+00:00

@sns

It looks like your VM does not have a DNS server configured at all.

If this is a Dev/Test environment, I would suggest you to to deploy a new VM altogether.

If you are interested in troubleshooting this VM,

1.First your VM must have a proper DNS configuration.

Ideally, this is how a DNS lookup output should appear for a Linux Distros

The 127.0.0.53 IP used here refers to a service running locally on your linux VM taking care of DNS.

Since you are not getting a DNS server, you should manually add a DNS server.

Run sudo vi /etc/resolv.conf

Add a line nameserver 168.63.129.16 after the comments.

Save and close the file

Now DNS resolution will use Azure Wireserver IP and would look like below

2.Once DNS issue is resolved, we can check the connectivity issue.

Please share the results of creating a new VM or DNS troubleshooting of this VM.

nslookup www.google.com

Cheers,

Kapil
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-21T10:08:54.8833333+00:00

@sns

Reaching out to check if there are any questions on this.

Please let us know if we can be of any further assistance here.

Thanks,

Kapil
sns 9,246 Reputation points

2023-12-21T10:18:27.7966667+00:00

HI Kapil,

it is working now. You can close case. Thank you
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-21T10:27:48.02+00:00

@sns

You are most welcome.

I have summarized my comments and posted it as a new answer.

I would highly appreciate if you could Accept the answer and close this thread

Original posters help the community find answers faster by identifying the correct answer.

Thanks,

Kapil
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-22T12:05:28.28+00:00

@sns

Just checking in to see if the below answer helped. If this answers your query, please don’t forget to click "Accept the answer" and Up-Vote for the same, which might be beneficial to other community members reading this thread. And, if you have any further query do let us know.

Thanks,

Kapil
KapilAnanth-MSFT 49,536 Reputation points Microsoft Employee Moderator

2023-12-26T07:47:47.5266667+00:00

@sns

Reaching out to check if there are any questions on this.

Please let us know if we can be of any further assistance here.

Thanks,

Kapil

Please Accept an answer if correct.

Original posters help the community find answers faster by identifying the correct answer.

Answer 1

@sns

Welcome to the Microsoft Q&A Platform. Thank you for reaching out & I hope you are doing well.

I understand that you are unable to install a package on a Linux VM and would like to know if Azure platform might be blocking the connection.

From the error message, it appears connection time out is issued for the site,

"https://rhui4-1.microsoft.com/pulp/repos/content/dist/rhel9/rhui/9/x86_"

From the tests, we found out the VM does not have a DNS server configured at all.

deally, this is how a DNS lookup output should appear for a Linux Distros
The 127.0.0.53 IP used here refers to a service running locally on your linux VM taking care of DNS.
Since you are not getting a DNS server, you should manually add a DNS server.
Run sudo vi /etc/resolv.conf
Add a line nameserver 168.63.129.16 after the comments.
Save and close the file
Now DNS resolution will use Azure Wireserver IP and would look like below

You informed us the issue has been resolved now.

Kindly let us know if this helps or you need further assistance on this issue.

Thanks,

Kapil

Please don’t forget to close the thread by clicking "Accept the answer" wherever the information provided helps you, as this can be beneficial to other community members.

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How to check any firewalls rules for Virtual network and VM

1 answer

Your answer