+ Post New Thread
Results 1 to 14 of 14
Wireless Networks Thread, Weird IP problem.... in Technical; Stumbled across an odd problem on a small range of IPs. In a nutshell any PC or device given an ...
  1. #1

    Join Date
    Jul 2010
    Posts
    124
    Thank Post
    61
    Thanked 2 Times in 2 Posts
    Rep Power
    9

    Weird IP problem....

    Stumbled across an odd problem on a small range of IPs. In a nutshell any PC or device given an IP in the range **.**.16.200 to **.**.16.248 cannot access our website (webserver on **.**.16.250)

    They can access/ping the 4 main servers ok (**.**.16.249, **.**.16.251, **.**.16.252) but not **.**.16.250.

    This is the same for static or dhcp reservations for those IPs.

    Any ideas?

  2. #2

    glennda's Avatar
    Join Date
    Jun 2009
    Location
    Sussex
    Posts
    7,817
    Thank Post
    272
    Thanked 1,138 Times in 1,034 Posts
    Rep Power
    350
    Is the webserver internal? and a VM?

  3. #3

    Join Date
    Jul 2010
    Posts
    124
    Thank Post
    61
    Thanked 2 Times in 2 Posts
    Rep Power
    9
    We have an odd setup but yes it is internal.

    We have 2 host webservers running on **.**.17.249 and **.**.17.200 that share the guest server - **.**.16.250

    These run linux and we have no control over these! They were setup and are run by our LEA.

  4. #4

    glennda's Avatar
    Join Date
    Jun 2009
    Location
    Sussex
    Posts
    7,817
    Thank Post
    272
    Thanked 1,138 Times in 1,034 Posts
    Rep Power
    350
    Quote Originally Posted by mcnallyfc View Post
    We have an odd setup but yes it is internal.

    We have 2 host webservers running on **.**.17.249 and **.**.17.200 that share the guest server - **.**.16.250

    These run linux and we have no control over these! They were setup and are run by our LEA.
    You might find that the VM host uses the addresses for the virtual bridge. I have it here after we increased the DHCP scope which means the range the bridge runs on cannot contact any of our vm's! not much you can do apart from block them out of the DHCP scope!

  5. Thanks to glennda from:

    mcnallyfc (13th December 2010)

  6. #5

    Join Date
    Jul 2010
    Posts
    124
    Thank Post
    61
    Thanked 2 Times in 2 Posts
    Rep Power
    9
    Hi Glennda, thanks for your help on this.

    With the webservers being linux and having no access to them - we are a little stuck as the admin guy says he isnt sure what virtual bridges are. Im trying to point him in the right direction but my experience is all in Windows OS' and have no idea how to approach it in linux.

    Is your system linux? where would you find such settings?

  7. #6

    glennda's Avatar
    Join Date
    Jun 2009
    Location
    Sussex
    Posts
    7,817
    Thank Post
    272
    Thanked 1,138 Times in 1,034 Posts
    Rep Power
    350
    It all depends if they are running the webservers as virtual machines ontop on the linux servers - or have installed the machine as a virtulization host.

    If you type ifconfig it should give you all the ip details just like ipconfig /all does

    if you post that up will take a look and see if you are using virtual bridges

    T
    Last edited by glennda; 16th December 2010 at 09:57 AM.

  8. Thanks to glennda from:

    mcnallyfc (17th January 2011)

  9. #7

    Join Date
    Jul 2010
    Posts
    124
    Thank Post
    61
    Thanked 2 Times in 2 Posts
    Rep Power
    9
    still getting this problem

    Have done more testing by testing switches etc by using laptop and assigning affected IP and plugging into different switches etc but same problem. Problem still exists when pinging/tracert IP or name.

    Trying to get more info from the webserver guy but going slow at the moment. To me it seems a problem in the webserver setup giving access to those IPs (like glennda suggests) but need to prove it.

  10. #8

    Join Date
    Jul 2010
    Posts
    124
    Thank Post
    61
    Thanked 2 Times in 2 Posts
    Rep Power
    9
    ok the setup of the webservers confuse me - apparently we have 2 physical servers with above IPs and one host that swaps between the pair of them (with its own ip address). The host that swaps between them is a guest?

    Im struggling to get more information on this....

  11. #9

    glennda's Avatar
    Join Date
    Jun 2009
    Location
    Sussex
    Posts
    7,817
    Thank Post
    272
    Thanked 1,138 Times in 1,034 Posts
    Rep Power
    350
    Quote Originally Posted by mcnallyfc View Post
    ok the setup of the webservers confuse me - apparently we have 2 physical servers with above IPs and one host that swaps between the pair of them (with its own ip address). The host that swaps between them is a guest?

    Im struggling to get more information on this....
    It sounds as through they are vm's running on virtual hosts for live migration.

    Toby

  12. Thanks to glennda from:

    mcnallyfc (17th January 2011)

  13. #10

    Join Date
    Jul 2010
    Posts
    124
    Thank Post
    61
    Thanked 2 Times in 2 Posts
    Rep Power
    9
    Quote Originally Posted by glennda View Post
    It sounds as through they are vm's running on virtual hosts for live migration.

    Toby
    Thanks for info - this setup, could this still be accountable for the IP problem? i.e. still running virtual bridges?

    As i dont fully understand the setup im struggling to push for more work to be done looking at webserver for the issue

  14. #11

    glennda's Avatar
    Join Date
    Jun 2009
    Location
    Sussex
    Posts
    7,817
    Thank Post
    272
    Thanked 1,138 Times in 1,034 Posts
    Rep Power
    350
    Quote Originally Posted by mcnallyfc View Post
    Thanks for info - this setup, could this still be accountable for the IP problem? i.e. still running virtual bridges?

    As i dont fully understand the setup im struggling to push for more work to be done looking at webserver for the issue
    Yes you have one or two physical machines connected to a shared storage which host multiple machines.

    Ask for a copy of the ipconfig on the machines and post it up and i will take a look. Also find out which software they are using for a hypervisor.

    This is how the system would look here

    Apart from their is two sets of hardware and the machine can swap between them when needed.

    Toby

  15. Thanks to glennda from:

    mcnallyfc (17th January 2011)

  16. #12

    Join Date
    Jul 2010
    Posts
    124
    Thank Post
    61
    Thanked 2 Times in 2 Posts
    Rep Power
    9
    copy of the ifconfig's

    eth0 Link encap:Ethernet HWaddr **:15:17:87:17:**
    inet addr:***.***.17.249 Bcast:***.***.19.255 Mask:255.255.252.0
    inet6 addr: fe80::215:17ff:fe87:1778/64 Scope:Link
    UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
    RX packets:70077188 errors:0 dropped:1088 overruns:0 frame:0
    TX packets:46549185 errors:0 dropped:0 overruns:0 carrier:0
    collisions:0 txqueuelen:1000
    RX bytes:13869522995 (12.9 GiB) TX bytes:43695666197 (40.6 GiB)
    Base address:0x2020 Memory:b8820000-b8840000

    eth1 Link encap:Ethernet HWaddr **:15:17:87:17:**
    inet addr:192.168.0.1 Bcast:192.168.0.255 Mask:255.255.255.0
    inet6 addr: fe80::215:17ff:fe87:1779/64 Scope:Link
    UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
    RX packets:6 errors:0 dropped:0 overruns:0 frame:0
    TX packets:60545 errors:0 dropped:0 overruns:0 carrier:0
    collisions:0 txqueuelen:1000
    RX bytes:384 (384.0 b) TX bytes:3881164 (3.7 MiB)
    Base address:0x2000 Memory:b8800000-b8820000

    lo Link encap:Local Loopback
    inet addr:127.0.0.1 Mask:255.0.0.0
    inet6 addr: ::1/128 Scope:Host
    UP LOOPBACK RUNNING MTU:16436 Metric:1
    RX packets:6521975 errors:0 dropped:0 overruns:0 frame:0
    TX packets:6521975 errors:0 dropped:0 overruns:0 carrier:0
    collisions:0 txqueuelen:0
    RX bytes:19113351722 (17.8 GiB) TX bytes:19113351722 (17.8 GiB)
    eth0 Link encap:Ethernet HWaddr **:15:17:87:3D:**
    inet addr:***.***.17.200 Bcast:***.***.19.255 Mask:255.255.252.0
    inet6 addr: fe80::215:17ff:fe87:3dac/64 Scope:Link
    UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
    RX packets:33660673 errors:0 dropped:0 overruns:0 frame:0
    TX packets:105774 errors:0 dropped:0 overruns:0 carrier:0
    collisions:0 txqueuelen:100
    RX bytes:4094543157 (3.8 GiB) TX bytes:8680419 (8.2 MiB)
    Base address:0x2020 Memory:b8820000-b8840000

    eth1 Link encap:Ethernet HWaddr **:15:17:87:3D:**
    inet addr:192.168.0.2 Bcast:192.168.0.255 Mask:255.255.255.0
    inet6 addr: fe80::215:17ff:fe87:3dad/64 Scope:Link
    UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
    RX packets:60536 errors:0 dropped:0 overruns:0 frame:0
    TX packets:66 errors:0 dropped:0 overruns:0 carrier:0
    collisions:0 txqueuelen:1000
    RX bytes:3880430 (3.7 MiB) TX bytes:10250 (10.0 KiB)
    Base address:0x2000 Memory:b8800000-b8820000

    lo Link encap:Local Loopback
    inet addr:127.0.0.1 Mask:255.0.0.0
    inet6 addr: ::1/128 Scope:Host
    UP LOOPBACK RUNNING MTU:16436 Metric:1
    RX packets:229 errors:0 dropped:0 overruns:0 frame:0
    TX packets:229 errors:0 dropped:0 overruns:0 carrier:0
    collisions:0 txqueuelen:0
    RX bytes:12104 (11.8 KiB) TX bytes:12104 (11.8 KiB)
    Last edited by mcnallyfc; 17th January 2011 at 12:28 PM.

  17. #13

    glennda's Avatar
    Join Date
    Jun 2009
    Location
    Sussex
    Posts
    7,817
    Thank Post
    272
    Thanked 1,138 Times in 1,034 Posts
    Rep Power
    350
    Doesn't look like they are using virtual bridges - although they could well be but just naming eth0 or eth1 (which probly isn't very good)

    So my theory goes out the window!

  18. Thanks to glennda from:

    mcnallyfc (17th January 2011)

  19. #14

    Join Date
    Jul 2010
    Posts
    124
    Thank Post
    61
    Thanked 2 Times in 2 Posts
    Rep Power
    9
    Damn! thanks for your help though - will be looking at rebooting the switches and playing around with those

SHARE:
+ Post New Thread

Similar Threads

  1. Weird Exchange problem.
    By Disease in forum Windows
    Replies: 5
    Last Post: 14th April 2010, 11:39 AM
  2. A most weird WSUS problem
    By mattx in forum Windows
    Replies: 12
    Last Post: 13th August 2009, 02:08 PM
  3. Weird monitor problem
    By sparkeh in forum Hardware
    Replies: 9
    Last Post: 12th June 2008, 10:13 AM
  4. Weird problem
    By akatuk in forum How do you do....it?
    Replies: 9
    Last Post: 10th October 2007, 08:30 PM
  5. Weird AD problem
    By SpuffMonkey in forum Windows
    Replies: 3
    Last Post: 29th March 2006, 10:57 AM

Thread Information

Users Browsing this Thread

There are currently 1 users browsing this thread. (0 members and 1 guests)

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •