Bash Script Compresses IPv6 Addresses to RFC Format Without External Tools

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A developer has published a pure Bash script that converts IPv6 addresses into their standard RFC-compressed form, such as shortening 2001:db8:0:0:0:0:0:1 to 2001:db8::1. The script requires no external dependencies beyond standard shell tools like bc and printf, making it lightweight and portable. It works by validating the address, identifying the longest consecutive run of zero segments, and replacing it with double-colon notation. An optional flag allows users to preserve the subnet prefix, such as /64, in the output. The tool is particularly useful in gbase database cluster configurations, where consistent IPv6 formatting simplifies deployment automation and address comparison.

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