davidnelson.net

Tag: network

  • iCloud with Custom Email Domains

    Google announced that users of their “G Suite legacy free edition” will soon have to start paying. I’ve begun exploring my options, the first of which was iCloud. (For those who don’t know, Apple recently started supporting custom email domains for users of any paid tier of iCloud.)

    Features

    • No additional cost if you already pay for iCloud
    • No need to check another account—your mail arrives in your existing iCloud inbox.
    • If you’re in a family sharing group you can let others have an account under your domain too.
    • Can add multiple domains.
    • Setup includes SPF and DKIM.

    Limitations

    • You can only add three email addresses per user.
    • It doesn’t seem to be possible to set up a wildcard that receives mail sent to any/all usernames at your domain.
    • You can’t give an account to someone who isn’t part of your family sharing group.
    • You can only add five domains. Yes that seems like a lot but it presents a problem for some of us.

    Verdict

    This is a compelling option for many people. It’s perfect for those who have a small number of domains all to themselves, or who have a domain they want to share with immediate family who are all in the Apple ecosystem. That covers a lot of non-business use cases.

    But personally I won’t be able to use it—at least not exclusively. I have more than five domains and some of them have users who are not in my family group. I may end up pointing one or two at iCloud, but I’ll have to look elsewhere for the rest.

    If it looks like iCloud would work for you, read on for a tour of the setup process.

    Setup

    To get stared, sign into your iCloud account and click on Account Settings.

    Main screen of iCloud after signing in.

    Scroll down to Custom Email Domain and click Manage.

    Click the Manage button under Custom Email Domain.

    If you’re part of a family sharing group you’ll be asked if the domain is just for you, or if you want to share it with your family members. It doesn’t appear to be possible to change this after the fact. At least not without removing and re-adding the domain.

    Who will use the domain: Only you, or you and your family group?

    You’ll be asked what domain you want to use. This has to be a domain (or subdomain) that you own and have the ability to manage DNS records.

    Enter the domain name you want to use.

    Next you’ll be asked to add and verify (via email) any existing addresses you want to use. I’m not sure why this is necessary since you could always add them after.

    Add existing email addresses if you were using this domain for mail with another provider.

    Now we need to update some DNS records using values Apple provides. Exactly how this is done and what it looks like will vary by DNS service, depending on whether it’s on a server you directly administer, or via a control panel provided by your registrar such as Hover, GoDaddy, etc. The records we need to add are:

    • Two MX (2) records which determine where mail should be delivered for your domain.
    • Two TXT records. One verifies ownership of your domain. The other is for SPF, which lets the world know which servers are allowed to send mail on your behalf.
    • One CNAME that points to a DKIM record. This identifies a key that will be used to sign mail sent from your domain. It helps other email servers know that the mail is legitimately from you and was not spoofed or tampered.
    DNS records to add to your domain.

    After creating or updating your records, click Finish set up. At this point Apple will reach out to your DNS server and check that the records were entered correctly.

    Confirm that you’ve updated your records.

    If everything looks good you’ll get a message confirming that it’s ready to go.

    The domain was added successfully.

    Now you can create any additional addresses that you didn’t enter earlier.

    That’s it! From here it’s just another email address you can use wherever you access your iCloud mail.

  • Scheduling Reboot of Motorola Cable Modem

    UPDATE: This no longer works for me because a recent firmware update removed the Restart command from the web interface.

    Periodically my Motorola SURFboard SB6141 cable modem stops talking to the outside world. I don’t know why, but restarting the modem fixes it every time. Rather than having to regularly power-cycle it by hand – or, heaven forbid, buy new hardware – I decided to schedule an automatic reboot.

    The modem itself doesn’t have a facility for automatic reboots, but it has a web page with a button to restart it! <http://192.168.100.1/cmConfig.htm> So all we have to do is automate the clicking of that button.

    If you have this model, or a similar one, this command should work. Just paste it into your terminal/console program and hit Enter, and see if you temporarily lose connectivity to the Internet. If you do, then it worked:

    /usr/bin/curl http://192.168.100.1/reset.htm -G -d reset_modem=Restart%20Cable%20Modem > /dev/null

    Once you verify it works for your modem, add it as a cron job. Mine looks like this, running daily at 4:30am:

    30 4 * * * /usr/bin/curl http://192.168.100.1/reset.htm -G -d reset_modem=Restart%20Cable%20Modem > /dev/null

    Tips:

    • The only real dependency is that you have curl installed. On Mac OS X, CentOS, and Debian it lives at /usr/bin/curl but if you’re using a different distro/OS you’ll want to make sure the path is correct.
    • Verify the IP of your cable modem is correct. For most/all Motorola models it’s 192.168.100.1 but try Googling yours if that doesn’t bring up a status page in a browser.
    • If the IP is correct, make sure the values passed by the restart button are the same as my example. (Go to the page that has the button, make sure that URL matches my example, then view source to make sure the name and value of the button match.)