Gentoo Forums
Gentoo Forums
Gentoo Forums
Quick Search: in
Confusion in Configuring Networks
View unanswered posts
View posts from last 24 hours

Goto page Previous  1, 2  
Reply to topic    Gentoo Forums Forum Index Networking & Security
View previous topic :: View next topic  
Author Message
Fred Krogh
Veteran
Veteran


Joined: 07 Feb 2005
Posts: 1018
Location: Tujunga, CA

PostPosted: Mon Dec 08, 2014 7:30 pm    Post subject: Reply with quote

I don't really need or even want a router, but I need wireless. I thought maybe their were switches that would put out a wireless signal, but the little looking I've done did not reveal such a thing. Thanks.
Back to top
View user's profile Send private message
WWWW
Tux's lil' helper
Tux's lil' helper


Joined: 30 Nov 2014
Posts: 143

PostPosted: Mon Dec 08, 2014 10:59 pm    Post subject: Reply with quote

This is interesting:

A system can have two interfaces with different subnets?

eth1 192.168.1.3
eth2 192.168.2.3

How do programs not get confused? I certainly can see this being useful. But won't get programs confuzzled?

Would it be possible to expand this?

eth1 192.168.1.3
eth2 192.168.2.3
eth3 192.168.3.3

And what it is the difference as opposed to have this?

eth1 192.168.1.2
eth2 192.168.1.3
eth3 192.168.1.4

Thanks!
Back to top
View user's profile Send private message
depontius
Advocate
Advocate


Joined: 05 May 2004
Posts: 3374

PostPosted: Tue Dec 09, 2014 12:35 am    Post subject: Reply with quote

Believe it or not, you've just asked a mouthful.

Really, subnets are defined by the "subnet mask", and in the case of the RFC-1918 network for 192.168.*.* the subnet mask is conventionally 255.255.255.0. You map that 255.255.255.0 over top of the 192.168.*.*, and what it really means is that for a given subnet, only the fourth number, the one after the last dot, is allowed to vary. So using your first/second examples, 192.168.1.3 and 192.168.2.3 are on different subnets, assuming you've got the normal 255.255.255.0 subnet mask. With your third example, 192.168.1.2 and 192.168.1.3 are both on the same subnet, and that applies pretty much regardless of the subnet mask. (I've used subnet masks to define very small subnets before on my home network, but it's not common.)

Why might you want multiple subnets? My home network currently has three subnets. I have a cable modem, and my appliance router plugs into that - first subnet. The back side of my appliance router is an 8-port switch, and 2 of those ports plug into a pair of (redundnat) bastion hosts, running secondary firewalls - second (DMZ) subnet. The back side of my redundant bastion hosts is my LAN, where the rest of the stuff on the home network connects. Right now my wireless router is plugged in as an access point on my LAN - so it's only using the wireless function, not the routing.

I'm thinking of changing things a bit in the near future, prompted by the Internet Of Things. I kind of want to get some of those Things, but it seems that they all need to phone home, and at least some of them (L.G. Smart TVs) phone home with information harvested from the LAN they're connected to. I want stuff like that on its very on subnet, that routes only to the internet, and not to my LAN. So that would probably mean plugging a wireless router into my DMZ with only a default route to the internet and its own subnet for my I.O.T.
_________________
.sigs waste space and bandwidth
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 42563
Location: 56N 3W

PostPosted: Tue Dec 09, 2014 7:57 pm    Post subject: Reply with quote

WWWW,

My KVM router has four subnets.

ppp0 is the big bad internet. PPPoE on eth0
eth1 is my DMZ on 192.168.10.0/24
eth2 is wy WAP on 192.168.54.0/24
eth3 is my wired protected network on 192.168.100.0/24

Apps don't get confused because the kernel looks after the interconnectivity.

I have separate wireless and wired networks
a) because I am paranoid
b) wireless is not permitted to connect to wired but it is allowed to respond if wired asks.

I have a few things an my wired network that like to phone home. They are all blocked by filtering on the destination port they try to connect to.
That results in logspam in wy firewall logs.
Did I mention that I'm paranoid?

Hmm maybe it actually has another subnet too. Being a KVM, its console is VNC on another subnet. 192.168.122.0/24 or something like that.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
WWWW
Tux's lil' helper
Tux's lil' helper


Joined: 30 Nov 2014
Posts: 143

PostPosted: Thu Dec 11, 2014 7:18 pm    Post subject: Reply with quote

NeddySeagoon wrote:

Did I mention that I'm paranoid?


Please stop excusing yourself, this set up is perfectly sane and it helps understanding the clear separation of areas and also helps implementing. I think your could be used in an office environment.

Now I only need to find out the commands to set up all that.

I kept thinking about separating traffic but I wasn't sure how to configure this. For instance one thing that was nagging me was a couple UDP traffic mixed with regular network. My idea was to have a different network for the internal UDP connections. Perhaps is not needed but for the sake of separating roles I wanted to do it.

thanks.


Last edited by WWWW on Thu Dec 11, 2014 7:22 pm; edited 1 time in total
Back to top
View user's profile Send private message
Fred Krogh
Veteran
Veteran


Joined: 07 Feb 2005
Posts: 1018
Location: Tujunga, CA

PostPosted: Thu Dec 11, 2014 7:22 pm    Post subject: Reply with quote

I'm back, sorry! I've learned a lot from the help already given.
Using a Windows 7 machine I finally got the router configured. The only ethernet connection my main computer has now is eth0. All seems to work, except apache is messed up. Thus
Code:
# /etc/init.d/apache2 start
 * Bringing up interface eth1
 *   config_eth1 not specified; defaulting to DHCP
 *   dhcp ...
 *     Running udhcpc ...
 *     start-stop-daemon: failed to start `/bin/busybox'                       [ !! ]
 * ERROR: net.eth1 failed to start
 * Bringing up interface eth2
 *   config_eth2 not specified; defaulting to DHCP
 *   dhcp ...
 *     Running udhcpc ...
 *     start-stop-daemon: failed to start `/bin/busybox'                       [ !! ]
 * ERROR: net.eth2 failed to start
 * ERROR: cannot start apache2 as net.eth1 would not start

I have looked and looked, and I can't see why apache would be looking for eth1 and eth2. Maybe things would all work if I could resolve this. Any ideas? Thanks.
Back to top
View user's profile Send private message
Fred Krogh
Veteran
Veteran


Joined: 07 Feb 2005
Posts: 1018
Location: Tujunga, CA

PostPosted: Thu Dec 11, 2014 7:49 pm    Post subject: Reply with quote

I have another problem. That windows 7 machine will not fetch mail, but gives no sign of the problem. It can access the web just fine. I have set it up to fetch from my server at 192.168.1.2. It will also not fetch from my site mathalacarte.com at 216.86.203.11. Is there something that needs to be said in the wireless router to make this work?
Back to top
View user's profile Send private message
NeddySeagoon
Administrator
Administrator


Joined: 05 Jul 2003
Posts: 42563
Location: 56N 3W

PostPosted: Fri Dec 12, 2014 8:59 pm    Post subject: Reply with quote

Fred Krogh,

If you have interfaces that you are not using, they may be required to be up so that the net service, which apache needs is considered up.

Read the comments in /etc/rc.conf and maybe adjust the rc_depend_strict setting.
_________________
Regards,

NeddySeagoon

Computer users fall into two groups:-
those that do backups
those that have never had a hard drive fail.
Back to top
View user's profile Send private message
Fred Krogh
Veteran
Veteran


Joined: 07 Feb 2005
Posts: 1018
Location: Tujunga, CA

PostPosted: Fri Dec 12, 2014 9:10 pm    Post subject: Reply with quote

Thanks Neddy! I was just in the process of posting the following when I got your last comment.

More info. The computers on the subnet can send mail, but can't access the pop-3 server on the same subnet. Some problems I had were only fixed by removing net.eth1 and net.eth2 from the default run level. It apparently was not sufficient to stop them as both postfix and apache were trying to access these access points. My web server now appears to be working, including with virutal hosts. So down to one problem only. The pop-3 part.

I note that /etc/init.d/postfix restart will not work. Postfix seems to think it is already stopped and it fails to start. postfix-reload does have the effect of changing the job numbers of the running postfix programs. At the moment I have no idea whether the problem is in postfix, or in the wireless router. or perhaps in dovecot. In the wireless router, I have had "Enable Port Trigger" set to no and to yes and in the latter case I have
Code:
25     TCP 25     TCP smtp
80     TCP 80     TCP http
50776  TCP 50776  TCP skype
110    TCP 110    TCP pop-3
In the virtual server section, I have
Code:
20:21  192.168.1.2  20:21  TCP  FTP Server(20:21)
25     192.168.1.2  25     TCP  SMTP Server(25)
80     192.168.1.2  80     TCP  HTTP Server(80)
110    192.168.1.2  110    TCP  POP3 Server(110)
22     192.168.1.2  22     TCP  ssh
50776  192.168.1.2  50776  TCP  skype

Perhaps something here will suggest why the mail can't be fetched? Thanks.
Back to top
View user's profile Send private message
Fred Krogh
Veteran
Veteran


Joined: 07 Feb 2005
Posts: 1018
Location: Tujunga, CA

PostPosted: Mon Dec 15, 2014 2:32 pm    Post subject: Reply with quote

Maybe enough progress to get this over the hump? But I'm still having problems with mail. I'm currently trying to set up a new account in my laptop that matches one on a Windows machine that will send but can't get mail. In the wireless router, I have set: Enable multicast routing to yes. That seems to be necessary. I have also enabled Port Trigger which now has the following data
Code:
Trigger Port Protocol Incoming Port Protocol Description
          25      TCP            25      TCP  smtp
          80      TCP            80      TCP  http
       50776      TCP         50776      TCP  skype
         110      TCP           110      TCP  pop-3
         106      TCP           106      TCP  pop-password
The virtual sever now has
Code:
Port Range    Local IP Local Port Protocol Description
        20 192.168.1.2         20      TCP ftp-data
        21 192.168.1.2         21      TCP ftp
        22 192.168.1.2         22      TCP SSH
        25 192.168.1.2         25      TCP SMTP Server
        80 192.168.1.2         80      TCP HTTP Server
       106 192.168.1.2        106      TCP POP3 Password
       110 192.168.1.2        110      TCP POP3 Server
     50776 192.168.1.2      50776      TCP skype
When trying to verify the password for the email account I'm seeing on my server things like this using wireshark
Code:
No. Time      Source         Destination  Protocol  Length              Info.
 12 8.16..  192.168.1.4   192.168.1.2     TCP       74      60031-110 [SYN} Seq=0 Win=29200 Len=0 MSS=1460 ...
 13 9.16..  192.168.1.4   192.168.1.2     TCP       74      [TCP Retransmission] 60031-110 [Syn] Seq=0 ...
 ...
Similar data shows up on the laptop, execpt with the source and destination data interchanged. Since the problem seems to be that the password could not be verified, I was expecting to see some 106 packets instead of the 110 packets, but maybe those need to go though first?

At this point, I don't know if I have a configuration problem in the router, or in dovecot or perhaps postfix. I would be very happy to provide more of the data from wireshark, if I had a better idea of what might be useful. Note that there is no problem in sending mail, just a problem in fetching it. The configuration of Thunderbird as far as the POP mail server is concerned are the same in all 3 cases, but it is only on my primary machine (where the mail server resides) that mail can be fetched.
Back to top
View user's profile Send private message
Display posts from previous:   
Reply to topic    Gentoo Forums Forum Index Networking & Security All times are GMT
Goto page Previous  1, 2
Page 2 of 2

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum