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Re: Ethernet is not started at boot




On Wed, Feb 07, 2018 at 10:02:18AM +0200, Michelle Konzack wrote:
However, the lead to the problem, that I need more then 256 IP addresses
and since I do not want to install my own  Linux  router  behind  my  3G
Gateway only to have 512 IP adresses or more, I decided to increaase the
network with 255.255.127.0. and if the IP is e.g. 192.168.4.12, then the
IP range become automatically 192.168.4.0-192.168.5.255.

As someone already pointed out, this is a bogus netmask. I recommend sipcalc as a handy tool for figuring out network information:

sipcalc 192.168.4.0/23
-[ipv4 : 192.168.4.0/23] - 0

[CIDR]
Host address		- 192.168.4.0
Host address (decimal)	- 3232236544
Host address (hex)	- C0A80400
Network address		- 192.168.4.0
Network mask		- 255.255.254.0
Network mask (bits)	- 23
Network mask (hex)	- FFFFFE00
Broadcast address	- 192.168.5.255
Cisco wildcard		- 0.0.1.255
Addresses in network	- 512
Network range		- 192.168.4.0 - 192.168.5.255
Usable range		- 192.168.4.1 - 192.168.5.254

sipcalc -4 "192.168.4.0 255.255.127.0"
-[ipv4 : 192.168.4.0 255.255.127.0] - 0

-[ERR : Invalid netmask]

sipcalc -4 "192.168.4.0 255.255.128.0"
-[ipv4 : 192.168.4.0 255.255.128.0] - 0

[CIDR]
Host address		- 192.168.4.0
Host address (decimal)	- 3232236544
Host address (hex)	- C0A80400
Network address		- 192.168.0.0
Network mask		- 255.255.128.0
Network mask (bits)	- 17
Network mask (hex)	- FFFF8000
Broadcast address	- 192.168.127.255
Cisco wildcard		- 0.0.127.255
Addresses in network	- 32768
Network range		- 192.168.0.0 - 192.168.127.255
Usable range		- 192.168.0.1 - 192.168.127.254