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Internet Problem

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Internet Problem

sharq.66
My internet stops working on server 2003 every half an hour.
Everytime i have to disable/enable network interface to access internet...

Seeking urgent advice..
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    Mehul Bhai

    Why are you re-posting the same question again and again!!!??? This is your third or fourth post regarding the same problem.
    Why not continue in the question already posted previously giving more details of the problem? This will help us here in helping you properly to solve your problem.

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    robo_dev

    I would assume that the ethernet connection on your server plugs into some sort of firewall/router, cable modem, or similar device?

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    sharq.66

    My server is ethernet port is connected to Linksys Router (WAG54G2)

    Ok..when i faced the problem i tried pinging www.google.com but unable to ping..But when i ping the google i got the reply..:O

    any advice ?

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    TobiF

    It seems the DNS server you're using isn't stable enough.
    I didn't understand what ping was successful, but if www.google.com fails, but google.com works, then the ip address of the second address may have been cached somewhere near your computer.

    What ip and dns settings do you have in your computer? (issue ipconfig /all in the command window)

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    sharq.66

    PPP adapter RAS Server (Dial In) Interface :

    Connection-specific DNS suffix :
    Description........: WAN (PPP/SLIP) Interface
    Physical Address : 00-53-45-00-00-00
    DHCP Enabled : No
    IP Address : 172.16.0.225
    Subnet Mask : 255.255.255.255
    Default Gateway :

    Ehternet adapter Local Area Connection :

    Connection-specific DNS suffix :
    Description : HP NC373i Multifunction Gigabit Server Adapter
    Physical Address : 00-1B-78-72-0E-C8
    DHCP Enabled : No
    IP Address : 172.16.0.2
    Subnet Mask : 255.255.255.0
    Default Gateway : 172.16.0.101
    DNS Servers : 172.16.0.2

    This is my ip configuration.

    When i face the problem last night i tried to ping www.google.com on command prompt, but i got no reply...
    When i tried to ping the google with google ip...i got the reply...

    Any furhter advice on this ?

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    0 Votes
    TobiF

    I note that your IP address (on the Ethernet interface) is the same as the DNS address.

    This means that whenever your computer needs to resolve an internet address (like www.google.com) into an ip address (like 173.194.36.104) it will contact... itself.

    So, there should be a DNS server running on your server. And this DNS server needs to be correctly configured.

    Do you need your server to handle dns requests? (This could be the case if you use logical addresses within your local network, or if you want it to maintain the dns records of some internet domain)

    If YES, then go find your DNS server program and its settings, there are some problems there.

    If NO, then contact your internet provider and ask them for the ip addresses to their DNS servers. You should get at least two different addresses from them. As an alternative, you could rely on, a public dns service, for instance - Google (In that case, enter the following dns addresses: 8.8.8.8 and 8.8.4.4)

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    sharq.66

    Sir, we are using windows server 2003 (172.16.0.2) as VPN server and also as Domain. We use to connect clients through this Domain. Now what IP address shall i assign in Preferred DNS Server ?

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    seanferd

    If not, the DNS server address is wrong, as it is the same as the IP address.

    DHCP is off, so you need to manually configure everything, don't forget.

    You have no default gateway in your PPP adapter.

    What is the Ethernet default gateway Default Gateway : 172.16.0.101. Is this a router? If so, what is the PPP adapter for?

    As to the VPN - DNS for the VPN is determined by the other end of the VPN tunnel.

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    TobiF

    This seems to be the domain controller itself. I believe that the dns resolver service on this machin is either absent or misconfigured (which might include pointing to an ISP dns with bad performance).

    The PPP adapter was for dial-in. And nowadays we're so used to ethernet that we sometimes forget that PPP, being point-to-point, don't use netmask and gateway, since there's only one way to go...

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    robo_dev

    If you launch the web browser on the server, you cannot get to google?

    Is the IP configuration for the server set to point to the router as the primary DNS server?

    Can you ping the DNS server of your ISP?

    Was this working normally at some point or is this a new install?

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    sharq.66

    yea..it was working fine absolutely fine...

    and the ip configuration is also correct...i use internet from the same ip configuration..

    its not a new install

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    seanferd

    Ping is not an internet tool. Frequently, ping and tracert will time out, as many routers and servers discard ICMP packets for security reasons.

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    robo_dev

    DNS servers are the first thing that seems to fail at any ISP.

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    seanferd

    Many do not respond to ICMP any more, in order to guard against DoS attacks.

    That being said, Google does respond to ping, so that test would be valid.

    But this is self-contradictory, or poorly phrased: <i>i tried pinging www.google.com but unable to ping..But when i ping the google i got the reply</i>. ??

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    robo_dev

    And also, are you able to get to the Web configuration page of your router when it fails?

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    sharq.66

    i can ping the router and also get web configuration page of router when my server fails to connect to internet

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    robo_dev

    show that you have an IP address?

    I assume that you are using either ADSL or cable modem to get to the Internet?

    Do you have a static IP address provided by your ISP or dynamic?

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    sharq.66

    The router status page shows IP address.

    We are using ADSL to get the internet.

    ISP provided us static IP

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    0 Votes
    robo_dev

    typically that's automatically assigned, so it should appear in your router.

    If, when your Internet connection is in failure mode, you can ping the DNS server of your ISP the whole time, then the next test would be to try surfing by IP address.

    For example, if www.google.com does not work, then goto 74.125.47.105 which is one of Google's IP addresses.

    It's possible that your DNS settings are incorrect in the server or perhaps you have a virus that is hijacking your DNS process.

    The utility to test DNS function is called nslookup. At the cmd prompt type nslookup www.google.com and you should get a valid response if DNS is working properly.

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    sharq.66

    Thanks for the post.

    When i tried nslookup www.google.com it says,

    ***Can't find server name for address 172.16.0.2 (server ip): Non-existent domain
    Server : UnKnown
    Address : 172.16.0.2

    Non-authoritative answer:
    Name : www.l.google.com
    Adresses : 74.125.79.147, 74.125.79.99, 74.125.79.104
    Aliases : www.google.com

    Any further assistance

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    0 Votes
    The 'G-Man.'

    208.67.222.222
    208.67.220.220

    then go home

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    0 Votes
    seanferd

    I'll bet it requires nxdomain responses from internet resolvers. This will break nxdomain unless the user creates an account and turns off the proxy and correction services, or creates exceptions.

    I can't even begin to count the reports of otherwise well-configured networks which rely on nxdomain before attempting local resolution. Ridiculous but true.

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    0 Votes
    robo_dev

    And also, are you able to get to the Web configuration page of your router when it fails?

  • +
    0 Votes
    Mehul Bhai

    Why are you re-posting the same question again and again!!!??? This is your third or fourth post regarding the same problem.
    Why not continue in the question already posted previously giving more details of the problem? This will help us here in helping you properly to solve your problem.

    +
    0 Votes
    robo_dev

    I would assume that the ethernet connection on your server plugs into some sort of firewall/router, cable modem, or similar device?

    +
    0 Votes
    sharq.66

    My server is ethernet port is connected to Linksys Router (WAG54G2)

    Ok..when i faced the problem i tried pinging www.google.com but unable to ping..But when i ping the google i got the reply..:O

    any advice ?

    +
    0 Votes
    TobiF

    It seems the DNS server you're using isn't stable enough.
    I didn't understand what ping was successful, but if www.google.com fails, but google.com works, then the ip address of the second address may have been cached somewhere near your computer.

    What ip and dns settings do you have in your computer? (issue ipconfig /all in the command window)

    +
    0 Votes
    sharq.66

    PPP adapter RAS Server (Dial In) Interface :

    Connection-specific DNS suffix :
    Description........: WAN (PPP/SLIP) Interface
    Physical Address : 00-53-45-00-00-00
    DHCP Enabled : No
    IP Address : 172.16.0.225
    Subnet Mask : 255.255.255.255
    Default Gateway :

    Ehternet adapter Local Area Connection :

    Connection-specific DNS suffix :
    Description : HP NC373i Multifunction Gigabit Server Adapter
    Physical Address : 00-1B-78-72-0E-C8
    DHCP Enabled : No
    IP Address : 172.16.0.2
    Subnet Mask : 255.255.255.0
    Default Gateway : 172.16.0.101
    DNS Servers : 172.16.0.2

    This is my ip configuration.

    When i face the problem last night i tried to ping www.google.com on command prompt, but i got no reply...
    When i tried to ping the google with google ip...i got the reply...

    Any furhter advice on this ?

    +
    0 Votes
    TobiF

    I note that your IP address (on the Ethernet interface) is the same as the DNS address.

    This means that whenever your computer needs to resolve an internet address (like www.google.com) into an ip address (like 173.194.36.104) it will contact... itself.

    So, there should be a DNS server running on your server. And this DNS server needs to be correctly configured.

    Do you need your server to handle dns requests? (This could be the case if you use logical addresses within your local network, or if you want it to maintain the dns records of some internet domain)

    If YES, then go find your DNS server program and its settings, there are some problems there.

    If NO, then contact your internet provider and ask them for the ip addresses to their DNS servers. You should get at least two different addresses from them. As an alternative, you could rely on, a public dns service, for instance - Google (In that case, enter the following dns addresses: 8.8.8.8 and 8.8.4.4)

    +
    0 Votes
    sharq.66

    Sir, we are using windows server 2003 (172.16.0.2) as VPN server and also as Domain. We use to connect clients through this Domain. Now what IP address shall i assign in Preferred DNS Server ?

    +
    0 Votes
    seanferd

    If not, the DNS server address is wrong, as it is the same as the IP address.

    DHCP is off, so you need to manually configure everything, don't forget.

    You have no default gateway in your PPP adapter.

    What is the Ethernet default gateway Default Gateway : 172.16.0.101. Is this a router? If so, what is the PPP adapter for?

    As to the VPN - DNS for the VPN is determined by the other end of the VPN tunnel.

    +
    0 Votes
    TobiF

    This seems to be the domain controller itself. I believe that the dns resolver service on this machin is either absent or misconfigured (which might include pointing to an ISP dns with bad performance).

    The PPP adapter was for dial-in. And nowadays we're so used to ethernet that we sometimes forget that PPP, being point-to-point, don't use netmask and gateway, since there's only one way to go...

    +
    0 Votes
    robo_dev

    If you launch the web browser on the server, you cannot get to google?

    Is the IP configuration for the server set to point to the router as the primary DNS server?

    Can you ping the DNS server of your ISP?

    Was this working normally at some point or is this a new install?

    +
    0 Votes
    sharq.66

    yea..it was working fine absolutely fine...

    and the ip configuration is also correct...i use internet from the same ip configuration..

    its not a new install

    +
    0 Votes
    seanferd

    Ping is not an internet tool. Frequently, ping and tracert will time out, as many routers and servers discard ICMP packets for security reasons.

    +
    0 Votes
    robo_dev

    DNS servers are the first thing that seems to fail at any ISP.

    +
    0 Votes
    seanferd

    Many do not respond to ICMP any more, in order to guard against DoS attacks.

    That being said, Google does respond to ping, so that test would be valid.

    But this is self-contradictory, or poorly phrased: <i>i tried pinging www.google.com but unable to ping..But when i ping the google i got the reply</i>. ??

    +
    0 Votes
    robo_dev

    And also, are you able to get to the Web configuration page of your router when it fails?

    +
    0 Votes
    sharq.66

    i can ping the router and also get web configuration page of router when my server fails to connect to internet

    +
    0 Votes
    robo_dev

    show that you have an IP address?

    I assume that you are using either ADSL or cable modem to get to the Internet?

    Do you have a static IP address provided by your ISP or dynamic?

    +
    0 Votes
    sharq.66

    The router status page shows IP address.

    We are using ADSL to get the internet.

    ISP provided us static IP

    +
    0 Votes
    robo_dev

    typically that's automatically assigned, so it should appear in your router.

    If, when your Internet connection is in failure mode, you can ping the DNS server of your ISP the whole time, then the next test would be to try surfing by IP address.

    For example, if www.google.com does not work, then goto 74.125.47.105 which is one of Google's IP addresses.

    It's possible that your DNS settings are incorrect in the server or perhaps you have a virus that is hijacking your DNS process.

    The utility to test DNS function is called nslookup. At the cmd prompt type nslookup www.google.com and you should get a valid response if DNS is working properly.

    +
    0 Votes
    sharq.66

    Thanks for the post.

    When i tried nslookup www.google.com it says,

    ***Can't find server name for address 172.16.0.2 (server ip): Non-existent domain
    Server : UnKnown
    Address : 172.16.0.2

    Non-authoritative answer:
    Name : www.l.google.com
    Adresses : 74.125.79.147, 74.125.79.99, 74.125.79.104
    Aliases : www.google.com

    Any further assistance

    +
    0 Votes
    The 'G-Man.'

    208.67.222.222
    208.67.220.220

    then go home

    +
    0 Votes
    seanferd

    I'll bet it requires nxdomain responses from internet resolvers. This will break nxdomain unless the user creates an account and turns off the proxy and correction services, or creates exceptions.

    I can't even begin to count the reports of otherwise well-configured networks which rely on nxdomain before attempting local resolution. Ridiculous but true.

    +
    0 Votes
    robo_dev

    And also, are you able to get to the Web configuration page of your router when it fails?