AzureパブリックIPアドレスについて

Question

Azure上に公開Webサーバを用意したいと思います。

オンプレ同様に”Azure Firewall"を用意し、その配下にVirtual Machinesを1台用意した場合

に必要なパブリックIPアドレスは１で問題ありませんか。また、将来的にVirtual Machines

を増やしたい場合にプレフィックスで8を選んでおけば固定IPアドレスとして8つ予約した事

になりますか。

パブリックIPアドレスを増やしたい場合に後で変更したとしても現在使用している静的IPアドレス

は変わってしまいますか

Answer 1

@賢治 金田

Thank you for reaching out on the Microsoft Q&A forum.

I am not familiar with the Japanese language so I am responding to your question here based on it's English translation. Please let me know if I have missed anything.

If you want to increase the number of IP addresses, you can reserve 8 fixed IP addresses by selecting 8 as the prefix. Will it be?

As documented here the following public IP prefix sizes are available in Azure:

/28 (IPv4) or /124 (IPv6) = 16 addresses

/29 (IPv4) or /125 (IPv6) = 8 addresses

/30 (IPv4) or /126 (IPv6) = 4 addresses

• /31 (IPv4) or /127 (IPv6) = 2 addresses

So, if you want to add 8 Public IP addresses you will have to create /29 (IPv4) prefix. You can follow the documentation here for add IP address to your firewall.

A static IP address that you are currently using, even if you change it later if you want more public IP addresses will it change

You can change this IP address, or you can keep the same IP attached to the firewall and add additional IP address as per your requirement.

Just FYI A firewall must have at least one public IP address associated with its configuration. You can't update the IP address if the firewall's existing IP has any destination network address translation (DNAT) rules associated with it. You can follow the documentation here to Change the public IP address for a firewall.

Hope this helps! Please let me know if you have any additional questions. Thank you!

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