The Soprani.ca project, and Cheogram in particular, is pretty big on bidirectional gateways.  The most popular Cheogram-hosted instance, so popular that it gets to own Jabber IDs on cheogram.com, is a bidirectional gateway to the telephone network.  How is it bidirectional?  Don’t you need a Jabber ID to use it?  Of course not!

Sending a Message

From any SMS-enabled device, add +12266669977, which is the gateway’s phone number.  Send the following SMS:

/msg someone@server.tld Hello!

The user with Jabber ID someone@server.tld should shortly receive your message.  If they reply, what you see will depend on their relationship to the gateway.  If they have a backend route set (such as JMP, Vonage, or Twilio) then you will get an SMS from their associated phone number.  If not, you will get a message from the gateway’s number like this:

<someone@server.tld says> Oh, fun!

Joining a Chatroom

An SMS user can also join exactly one chatroom at a time.  Send this to the gateway’s number:

/join someroom@conference.server.tld

You should receive a message with the current list of participants, after which you will start seeing messages sent to the room.  After this point, any SMS send to the gateway’s number that is not a valid command (such as /msg) will be sent to your joined room as a message.  You can send /help at any time to get a list of other commands for leaving, setting your nickname, etc.

Making a Voice Call

To call a Jabber ID, first enter it into this form then dial one of the access numbers and follow it up with the extension generated by the form.

The extensions are often very long, so the easiest way to dial them on Android is to create a contact with a phone number of the form:

+access_number,*10816etc

If you have trouble with one access number, try another one.  If the Jabber ID you wish to call is very long some access numbers may time-out waiting for you to dial all the digits.

This blog is powered by XMPP. That means it is federated over the Jabber network, it has a Jabber ID, and you can subscribe to it using a supporting Jabber client. One such client with support for subscribing, liking, and commenting is Movim. There are several public Movim instances including one hosted by upstream and one by chatterboxtown. Once you are logged in with a Movim instance, you can follow these steps to discover this blog and subscribe.

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3. If blog.jmp.chat is not yet known to this instance, you can use the search box to add it

   
4. After entering blog.jmp.chat in the search box and hitting enter, you may need to click away to any other Movim page and then come back to the Communities Servers area as before.

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8. New posts from the blog will now show up under News

    

You'll recall me warning recently that using Spamhaus data to protect your mail server is a bad idea if you're using open or public DNS resolvers . TL;DR? Spamhaus is worried about too much traffic via public channels but blocking is implemented in a way that makes it effectively intermittent and potentially confusing. You could be fine for weeks and then suddenly you start bouncing all inbound mail accidentally. Or you could be querying a resolver that never shows ANY bad IPs to block, losing you out on the good spam filtering benefit that you were hoping for.

Značky: #howto, #spamhaus, #dnsbls, #Network

How do I use OpenDKIM with multiple domain names on a single postfix server? That's a question I myself had when I first set up my current VPS to host my current email system. So I searched around a bit. I found this guide , but it's kind of a pain in. Too much heavy lifting.

So I tried this instead. It's a bit of a hacker trick nobody seems to mention online: In your opendkim.conf file, where you specify the domain, you can just include multiple domains here, separated by commas.

Instead of
domain example.com
Just put
domain example.com,example.org,mydomain3.com
In your opendkim.conf file.

Upside : Super easy.
Downside : All domains have to share the same DKIM key, because there's only one DKIM key setting in opendkim.conf.

It works fine. Though you specify the domain name when creating a DKIM key, there's nothing in the key that is actually domain-specific. At scale, this is insecure. At the hobbyist level, where I've got three domains running on my one server that send a grand total of 150 emails a day, it's not a concern.

You can also put an asterisk (*) to wildcard the domain setting in opendkim.conf. However, I don't recommend this, because it will try to sign all mail for any domain, without checking to see if a DKIM public key actually exists for that domain. So if you send or forward any mail at all for any other domain, that mail will end up with a broken DKIM signature attached to it. An example where this will happen and be very bad for you is mailing lists. Some mailing lists rewrite the from address to use their own domain to bypass DMARC concerns, but not all do, and some only do it sometimes. So I strongly recommend against using a wildcard here, unless you know what you're doing.

Značky: #opendkim, #llinux, #dkim, #howto, #postfix, #Network

Looking for guidance on how to create your BIMI logo file? Valimail has a pretty good guide that explains the requirements and they also explain what to keep in mind when creating your BIMI graphic SVG file. Starting with:

• Square
• SVG Tiny Portable/Secure format
• Solid background
• Published via HTTPS

SVG meaning a Scalable Vector Graphics file, and particular type of SVG called SVG Tiny Portable/Secure (SVG P/S) . The image has to truly be a vector graphic ; the overall SVG spec does allow you to embed a bitmap in a file but this isn't allowed for SVG P/S or BIMI usage.

The Valimail guide goes on to explain how to manually edit the SVG file to convert it to the SVG P/S spec. But if you don't feel like editing XML files by hand, download this converter application that the BIMI (AuthIndicators) Working Group has shared here. I've used the Macintosh version and it works fine. (You may need to tell your Mac that it's OK to run this application.)

I used the tool to create a BIMI logo for XNND.com , just to see if I could do it. I don't have a VMC and I send a very low volume of mail, so I don't expect it to show up anywhere, but at least it was pretty easy to do.

Značky: #bimi, #xnnd, #valimail, #howto, #Network

Need to export a file from Linux via email? Got uuencode ? Do you even remember uuencode ? It's how we used to encode files for file sharing, back before you were born. Because I'm old.

Here's a handy one-liner that will wrap your file up as a UUEncoded attachment and mail it to the address you specify. The email should come through with a properly formatted attachment that you can then download.

Just do this:
% cat file.zip | uuencode file.zip | mail recipient@example.com

Or you can get a bit fancier and add a subject line and a proper from address (if your system doesn't add one already):
% cat file.zip | uuencode file.zip | mail -s "Export of file.zip" -a "From: Me <sender@example.com>" recipient@example.com

Or you can do it as part of a shell script, with bits that look something like this:

FROM="Just Me <sender@example.com>"
TO="recipient@example.com"
FILE="file.zip"
cat $FILE | \
uuencode $FILE \
mail -s "Export of $FILE attached" \
-a "From: $FROM" \
$TO

I know there's probably some better way to do this, but this simple example has saved me endless amounts of time lately. I hope you find it useful, too.

Značky: #linux, #unix, #Network, #howto

If you’re here you probably know the essence of open source already. To us, open source means more than just open source code – it’s also the ethics and the community feeling that goes along with that. For us it means that the people working on Icinga are more than just who we see in […]

The post Contributing to Open Source appeared first on Icinga .

Značky: #How-tos, #Community, #howto, #Development, #Network, #contributing

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