Netmask installation question

[blind0ne]

Hi, i'm trying to install freebsd on vm, but i'm struggling with the netmask field which value is "fxfffffff0", but I need to assing 255.255.255.240/28.
What will be the fff form of this subnet notation?

 

[blind0ne]

it looks like it should be like "ff.ff.ff.f0", or I'm wrong somewhere?

 

[freejlr]

Yes, that is just the mask 255.255.255.240 only in hexadecimal or base 16 format.

You can specify the mask in decimal or hexadecimal example:

ifconfig em0 inet 192.168.1.3 netmask 255.255.255.240 up

or

ifconfig em0 inet 192.168.1.3 netmask 0xfffffff0 up

 

[SirDice]

Cheat sheet: https://www.ietf.org/rfc/rfc1878.txt

 

[blind0ne]

Yes, that is just the mask 255.255.255.240 only in hexadecimal or base 16 format.

You can specify the mask in decimal or hexadecimal example:

ifconfig em0 inet 192.168.1.3 netmask 255.255.255.240 up

or

ifconfig em0 inet 192.168.1.3 netmask 0xfffffff0 up

thanks, just been high on coffee.

 

[covacat]

also ifconfig iface0 a.b.c.d/NN works

 

[smithi]

also ifconfig iface0 a.b.c.d/NN works

Yes, where "inet a.b.c.d/28" is equivalent to "inet a.b.c.d netmask 255.255.255.240" - to be pedantically thorough.

 

[mer]

Yes, where "inet a.b.c.d/28" is equivalent to "inet a.b.c.d netmask 255.255.255.240" - to be pedantically thorough.

This is a case of "sixes and threes". I honestly prefer the CIDR notation ( /28 ) over netmask because sometimes people think think they can do a netmask of 255.237.255.228.

 

[smithi]

This is a case of "sixes and threes". I honestly prefer the CIDR notation ( /28 ) over netmask because sometimes people think think they can do a netmask of 255.237.255.228.

Oh, absolutely. We ran a /26 for years, later reduced to /28 as price per IP address increased dramatically, later a /29 running from home until 2019.