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Showing posts from October, 2017

tc classid range

TC minimum and maximum "classid" and "flowid"
Playing a lot with TC on Linux, I one time wondered what is the min and max value of the "classid" and "flowid".

Looking to the man page, I found:
IDs consist of a major number and a minor number, separated by a
colon - major:minor. Both major and minor are hexadecimal numbersand are limited to 16 bits. There are two special values: root is
signified by major and minor of all ones, and unspecified is all
Well, to get more precise, I also put here what is the relationship between hexadecimal and bits:
Hexadecimal numerals are widely used by computer system designers and programmers. As each hexadecimal digit represents four binary digits (bits), it allows a more human-friendly representation of binary-coded values. One hexadecimal digit represents a nibble (4 bits), which is half of an octet or byte (8 bits) I hope this helped to understand several details we sometimes skip when in a rush.