how it routes and network question

Bruce Forster bruce at tubes.net.au
Mon Dec 21 17:45:43 CST 2009


<SNIP>

1/ How can I know those servers are same network as those net mask is /32
if not the same network, I have problem when two servers are slowing
in transferring files
</SNIP>
Check the subnet mask, i doubt its going to be 255.255.255.255

<SNIP>
2/ lf  the network card in server has problem and need change another
one, will my ip address change to another ip address also?
</SNIP>
Yeah well thats how dhcp works, via ma caddy, i guess you can always spoof
your old mac address.

<SNIP>
3/ why hosting company is using /32 and dhcp? what is advantage? ls it
easy for administration?
</SNIP>
Im guessing because the users are to stupid to understand what a subnet
mask/gateway is its just easier to get the mac address and assign it to a
user then let the user assign a ip.


Normally in a co-location setup its not like this, inless its very cheap
hosting.

My co-location has the following setup, and this is how MOST networks should
be run.

Core router using BGP to transit providers, and other local peers.
Switched network useing ospf to handle the routes and also VLAN's for the
customers subnets.

So customer should get a vlan assigned to them (which they have no need to
know what the number is, they are handed a access mode port.
Customers also issued a /30 (at least) in most cases a customer will get a
/29 or /28 depending on what they need.
In this case of a /30 its a total of 3 address's
1, GATEWAY (put on the ISP/HOST switch
2, IP ADDRESS FOR SERVER TO USE
3, BROADCAST ADDRESS.

Heres an eg of a /30:

Address:   192.168.1.1          11000000.10101000.00000001.000000 01
Netmask:   255.255.255.252 = 30 11111111.11111111.11111111.111111 00
Wildcard:  0.0.0.3              00000000.00000000.00000000.000000 11
=>
Network:   192.168.1.0/30       11000000.10101000.00000001.000000 00
HostMin:   192.168.1.1          11000000.10101000.00000001.000000 01
HostMax:   192.168.1.2          11000000.10101000.00000001.000000 10
Broadcast: 192.168.1.3          11000000.10101000.00000001.000000 11
Hosts/Net: 2                     Class C, Private Internet


Heres an eg of a /29:

the % ipcalc 192.168.1.1/29
Address:   192.168.1.1          11000000.10101000.00000001.00000 001
Netmask:   255.255.255.248 = 29 11111111.11111111.11111111.11111 000
Wildcard:  0.0.0.7              00000000.00000000.00000000.00000 111
=>
Network:   192.168.1.0/29       11000000.10101000.00000001.00000 000
HostMin:   192.168.1.1          11000000.10101000.00000001.00000 001
HostMax:   192.168.1.6          11000000.10101000.00000001.00000 110
Broadcast: 192.168.1.7          11000000.10101000.00000001.00000 111
Hosts/Net: 6                     Class C, Private Internet

Hope this makes sence.

Regards,

Bruce






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