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A comment on There’s more than one way to write an IP address.

Re:There’s more than one way to write an IP address by Ididntdothis on Tuesday July 09, 2019 @08:01AM (#20390913)
The different notations tripped us up big time a while ago at my company. A class of our devices used to get their machine name set from the serial number in the BIOS. On the older models these started with letters. Then we got a new model and the serial numbers on these were just long numbers. So far so good.

After a while we noticed that a lot of them (around 30%) didn't work on the network. It took a while to figure out that some of the serial numbers got interpreted as octal IP addresses so pinging them didn't resolve through DNS but instead went straight to the (wrong) IP.

In hindsight this could have been predicted but it just shows that often a design that made sense when it was created can cause huge headaches later on. Now we prefix all serial numbers with some letters to make sure they don't get misinterpreted.

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Re:There’s more than one way to write an IP address by js2 on Tuesday July 09, 2019 @10:01AM (#20391797)
You should have been able to ping them using an FQDN but I can see how it would be confusing to have to do that.
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Re:There’s more than one way to write an IP address by heavenlyblue on Tuesday July 09, 2019 @09:39AM (#20391575)
Why not base64 them?

Do you actually use serial numbers anywhere else?

Why not generate a random name instead?

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Re:There’s more than one way to write an IP address by Ididntdothis on Tuesday July 09, 2019 @09:49AM (#20391688)
The serial numbers are on the back of the devices so it’s nice to be able to correlate them with the network name. As I mentioned now we prefix them with a few letters to avoid being misinterpreted.
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Re:There’s more than one way to write an IP address by Thorrez on Tuesday July 09, 2019 @11:12PM (#20398895)
Base64 needs 64 unique characters, but domains names don't have 64 unique characters. Also base64 could result in pure numbers as its output, leading to the exact same problem.
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