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  • can't see local subnet

    okay, i'm the support guy/jr. admin at our company. (actually, i'm the only admin. yikes!) here's the situation i walked into and am unable to resolve:

    here at corporate, we are on the192.168.2.x subnet (w2k3 standard, sp2). at our warehouse, they are on the 192.168.0.x subnet (also w2k3 standard, sp2). the sites are wan'd via vpn in our sonicwall firewalls, one at each location.

    from my local pc on the 2.x subnet, when i browse the network, i can see all of the servers and pc's on the 0.x subnet, but none of the local 2.x boxes. this is true for several of our boxes here. well no, biggie. i can map to shares on 2.x subnet if i have to. BUT...

    our local dc, which is also the dns server, cannot see the local 2.x subnet either, but can see the 0.x subnet. obviously, i need the dc to function 100%. we had a consultant come in and look at our settings. he recommended a few changes, but none of them seemed to help with this particular issue.

    so, the corporate dc is 192.168.2.102. the warehouse dc is 192.168.0.102. on the 2.102 box, we serve dns as 192.168.2.102, 192.168.0.102. on the 0.102 box, we serve dns as 192.168.0.102, 192.168.2.102.

    everything from the warehouse side seems to be okay. it's just here at corporate that things are screwy. i'm sure there's a boatload of info i haven't provided, but i can answer any questions you might have.

    anyone have any advise for me?

    thx a mil!

  • #2
    Re: can't see local subnet

    do your clients rely on DHCP to receive an IP address?

    if so, do you see any of the stations in the "address leases" section of the subnet in question?
    its easier to beg forgiveness than ask permission.
    Give karma where karma is due...

    Comment


    • #3
      Re: can't see local subnet

      well, now. that's interesting. yes, all the clients are on dhcp. in the lease table, almost every client has 2 entries, some seconds apart, other a week or so apart. what does this tell us?

      btw, thx for your help on this.

      Comment


      • #4
        Re: can't see local subnet

        I'm not sure but I don't believe that DHCP has anything to do with seeing the computers on the network or not. As for the dual leases I suspect that the computers are connecting to a wired LAN and a WAP so they each have two NIC's and therefore get two ip addresses.

        Have you checked to make sure that File and Print Sharing is turned on and that NetBIOs over TCP/IP is enabled. If not, then you won't see the machines on the network (I'm assuming that you can ping by FQDN and ip address).

        Comment


        • #5
          Re: can't see local subnet

          okay, the two leases makes sense, mostly. i'm never wired, so i don't know why i'd have 2 leases. but, let's go with the idea that that's not the issue.

          file and print sharing is on by default on all clients (AFAIK. i haven't gone to everyone's desk to verify, but it's a damn safe bet). netbios is set to default, which is to get netbios settings from the dhcp server. sounds like a good thing to check. but, i've gone into the dhcp server and don't see anything obvious like 'serve netbios.'

          you think i'm in the right area here? what should i look at next?

          Comment


          • #6
            Re: can't see local subnet

            I'm assuming that everything on the network is working normally (client logons, resource access, internet connection, etc.) other than not being able to see anything. Can you give some more info, when you say you can't see anything you are referring to Network Neighborhood right? Is Windows firewall or a third party software firewall installed on the machines? Are you using WINS? The default NetBIOS settings are to get them from DHCP unless DHCP doesn't set any NetBIOS options, then NetBIOS over TCP is enabled. Unless you are setting a NetBIOS option through DHCP I don't think there's anything wrong there. Can you ping any machine by NetBIOS name? I'm assuming you can ping by FQDN or ip address.

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            • #7
              Re: can't see local subnet

              yup, everything else works normally. and yup, i can ping by the netbios name. check this out:

              i changed my pc's tcp/ip settings to use netbios over ip instead of netbios from the dhcp server. nothing changed. i then changed it back. i can now browse the network! so, i went to another pc with the same problem and did the same thing. didn't work. sigh...

              Comment


              • #8
                Re: can't see local subnet

                Hi,
                Are resources in the corporate network showing up under the remote office networks?
                Just to bring you back to the dhcp thing, can you do an
                Code:
                ipconfig /all
                on one of the affected PC in the corporate network? Are they connecting to the right DHCP server?

                Also are you using sites?
                I don't know anything about (you or your) computers.
                Research/test for yourself when listening to free advice.

                Comment


                • #9
                  Re: can't see local subnet

                  Are the workstation and server services running on each machine? Are any of the computers running Windows Vista?

                  Comment


                  • #10
                    Re: can't see local subnet

                    i only suggested DHCP as a basic connectivity test. i figured if DHCP was being relayed, then there was connectivity.

                    that is an odd problem, none the less.

                    i would still err on the side of qwertys suggestion that there is a firewall in the way...

                    maybe from a workstation that is on the remote site, use angryIP and see if the standard filesharing ports are open, and the other important ones... 21, 23, 137, 138... 443 and so on.

                    can you perform a capture on the firewall and log for connections comming from the remote site? verify that there is a syn going and see if thee is a syn ack comming back... and the same at the same time on the other firewall (if its there) and see where the packets are stopping.
                    its easier to beg forgiveness than ask permission.
                    Give karma where karma is due...

                    Comment


                    • #11
                      Re: can't see local subnet

                      hey! here's some more fun info...

                      i spent a little time this weekend working on this on the local dc, the one that really matters. changing to netbios over ip and then back to default didn't help. i then changed the speed & duplex from auto to 1gb. hey! there's the local subnet!! hey! where's the remote subnet?? i put the adaptor back to auto.

                      so, this morning i had an idea...i checked the remote dc's adaptor and that's also set to auto. tonight or tomorrow, i'm gonna change both to 100/full or 1000/full and see how that goes.

                      what do y'all think?

                      oh, and thanks for sticking with me this far!!

                      Comment


                      • #12
                        Re: can't see local subnet

                        okay, so i tested out a plethora of speed/duplex combos with varying results. i am copying and pasting the e-mail i sent to my boss last night about 10pm:
                        Originally posted by me to my boss
                        okay. so, i changed both adaptors to 1000/full. i could then see SO from SO and VN from VN, but that was it. i then changed them both to 100/full and got the same results. i then changed them both to 100/half. then i could see VN from VN and nothing from SO. i then changed SO back to auto, and could see everything in both SO and VN from SO, but still only VN from VN. so, i bumped up VN to 100/full and still could only see VN from VN, but in SO, i could now only see SO PLUS about 5 of the VN boxes. i then bumped VN up to 1000/full with the same results. i then changed VN back to auto, with the same results. so...

                        everything is back to the way it was (both on auto). but the browsing capabilities of both dc's have changed: VN can now see only VN, whereas before it could see everything. SO can now see SO PLUS pdpwpvn and several VN desktops, whereas before, it could see everything in VN, but only VN.

                        OKAY, HOLD ON...

                        i was just going to send this and decided to double-check everything on the dc's first. after about a 10 minute 'refresh' time, i can now see all of SO and VN from SO (yay!). i can still, however, only see VN from VN. of course, none of this affects any mappings, only browsing ability. so, ultimately, i feel like i made a step in the right direction. still, i'm a bit confused and this needs to get sorted out.
                        SO is sherman oaks (corporate). VN is vernon (warehouse).

                        this is where we now stand. can anyone help me make a bit of sense of this?

                        thx again!

                        Comment


                        • #13
                          Re: can't see local subnet

                          Network Neighborhood (or My Network Places) is populated by way of SMB and NetBIOS. If the Workstation and Server services are running on all computers then I think maybe you have a problem with the routers or switches not passing broadcasts as all computers will advertise themselves by way of broadcasting on each local segment. Technically the broadcast traffic from one subnet should not be directed through a router to the other subnet so maybe you will need to set up a WINS server and configure all computers on each subnet to use WINS.

                          Comment


                          • #14
                            Re: can't see local subnet

                            I agree with Joeqwerty..
                            However I don't see any use of "my network places". Why is this so important...?

                            I think maybe you have a problem with the routers or switches not passing broadcasts as all computers will advertise themselves by way of broadcasting on each local segment
                            I have to explain that this is not a problem but it's just how it works.
                            A router won't pass broadcast traffic. It creates seperate broadcast domains. Thank god.
                            Also switches will pass broadcast traffic within each VLAN except from the source port.
                            Marcel
                            Technical Consultant
                            Netherlands
                            http://www.phetios.com
                            http://blog.nessus.nl

                            MCITP(EA, SA), MCSA/E 2003:Security, CCNA, SNAF, DCUCI, CCSA/E/E+ (R60), VCP4/5, NCDA, NCIE - SAN, NCIE - BR, EMCPE
                            "No matter how secure, there is always the human factor."

                            "Enjoy life today, tomorrow may never come."
                            "If you're going through hell, keep going. ~Winston Churchill"

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                            • #15
                              Re: can't see local subnet

                              Originally posted by Dumber View Post
                              I agree with Joeqwerty..
                              However I don't see any use of "my network places". Why is this so important...?
                              here's how the whole thing started: we just purchased the backup exec remote agent for unix, so we could back up our graphics server. when i went to install the agent, i realized that i couldn't see the local subnet, of course including the aforementioned graphics server. thus my quest began. anyways, more info...

                              turns out, we're having some master browser issues. we've got a full-blown network guy coming in next week. hopefully, he'll figger this stuff out and edumacate (yeah, edumacate!) me in the process. i'll let y'all know how it pans out.

                              thx for all the input!

                              Comment

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