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vpn subnet mask issue

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9 replies

by mashiah

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hi,

i have been a rras server as a vpn server and gave the vpn clients static ip from range.

the subnet mask is 255.255.255.255 and i can ping between vpn clients but cannot see them on the network.

is there a way to change subnet mask to 255.255.255.0 ?

anyway to get broadcasting between vpn clients?

i've read somewhere to try WINS sever for resolving NETbios and it didnt worked.

any ideas?

thanks,

David.

9 replies

by oldbaritone

Since these are all static addresses, you should be able to change the subnet mask, but you need to change it on all of the clients at the same time.

255.255.255.0 subnet mask will make x.x.x.255 the broadcast address.

Whether or not the clients will actually recognize the broadcast address is a different question that may depend on the VPN client software.

Since you're using static IP, if you're trying to locate a specific machine on the VPN, you could put it as an entry in HOSTS if you can't get WINS/NB to work properly.

by mashiah

ive tried with WINS Server and i have name resolution but still no broadcasting.
can u explain me where (witch window or menu) can i change subnet mask for vpn user?
tnx David.

by cg it

better yet, simply have DHCP provide the RRAS pool.

by oldbaritone

just assign the address pool. If you want certain machines on certain specific addresses, use DHCP with reservations.

by mashiah

tried with dhcp but it still gave 255.255.255.255 subnet mask

by cg it

if this is a RRAS box, then when you configured RRAS, you did so providing either a static pool or DHCP supplied pool. DHCP supplied pool uses that addressing and subnet mask.

unless your network DHCP is using the all 1s subnet mask which wouldn't work, then it will use it's subnet mask.

So reconfigure your RRAS.

by mashiah

using the all 1s subnet ?
what do you mean?
if i have 2 scopes ?

by cg it

when subnetting, the subnet mask determines the network portion of the address vs the host portion of the address. In binary, 1s & 0s 1s represent the mask. 255 = all 1s in an octet 128+64+32+16+8+4+2+1 = 255.

subnet mask of 255.255.255.255 represents all 1s in all 4 octets therefore there are no hosts bits or zeros therefore the destination network address must match exactly [network address not host as there are no hosts bits shown / no zeros].

So for your RRAS box, the subnet you use to provide addresses to remote clients on the local network, must be the addressing and subnet mask of the local network for RRAS clients to gain access to local lan resources.

you do that by configuring RRAS to use DHCP, & a DHCP relay agent where DHCP sets aside a block of local LAN addresses for RRAS clients eg the RRAS PPTP/L2TP miniports.

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