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I am having a weird TCPIP problem which I would need some input:-
We have a TCPIP LAN (just one subnet) and a firewallgateway to the internet. We use win98 as client computers. Ocasionally, the win98 clients will be unable to get to the internet. When this happens, I can ping any internal addresses and the default gateway. However, I can't ping anywhere outside. At first, I though our ISP is down but when I checked my neighbour, he was fine with browsing the internet. So I rebooted my 98 box and it comes right back. It works fine for a random time (couple of hours/couple of days) and same thing happens again. Reboot will usually fix it for a while.
If my TCPIP stack is bad, then I should not be able to ping internally. If ISP is bad, then my neighbour will be unable to browse when my PC is down. I noticed yesterday when my PC was down, the subnet mask has changed from 255.255.255.0 to 255.0.0.0. We use DHCP and I have found am unused address so I'm using this static address on my box. It seems to be running better but I did have a lost connectivity this morning.
Our hardware:-
- Cisco Catalyst 4000 series switching hub, 10/100 auto sensing
- we do have a mix of cat 3 and cat 5 cabling (I am assume the hub will be able to isolate if a problem with a cable drop occur)
Thanks in advanced !
- ML
nethead
10-31-2000, 07:23 PM
Things to think about and things to check.
The fact that you can ping ip addresses on your local subnet proves that your MAC layer 2 is working well. It seems that you are having the problem when you are at layer 3 sending packets across subnets using the default gateway. If your subnet mask is changing for some reason you will definately have some weird problems.
Are you getting DHCP services from your local DHCP server or from your ISP?
If it's your server, what is your lease time? Some DHCP servers/clients can have problems when the lease time is set to low (like a few hours). The fact that your subnet mask changed may indicate a DHCP problem, since the mask, default gateway and DNS server information is sent in the DHCP packet.
Something else to think about. Are you using the ip address or a host name in the ping command? Is your ISP providing DNS services for you? You may be having name resolution problems. Maybe caused by a DHCP problem or a DNS server problem.
Sure sounds like a DHCP problem of some sort. Try a release and renew command before you reboot next time. Command is winipcfg /release_all winipcfg /renew_all.
Good Luck
nethead
------------
ML at 8/25/00 12:24:49 PM
I am having a weird TCPIP problem which I would need some input:-
We have a TCPIP LAN (just one subnet) and a firewallgateway to the internet. We use win98 as client computers. Ocasionally, the win98 clients will be unable to get to the internet. When this happens, I can ping any internal addresses and the default gateway. However, I can't ping anywhere outside. At first, I though our ISP is down but when I checked my neighbour, he was fine with browsing the internet. So I rebooted my 98 box and it comes right back. It works fine for a random time (couple of hours/couple of days) and same thing happens again. Reboot will usually fix it for a while.
If my TCPIP stack is bad, then I should not be able to ping internally. If ISP is bad, then my neighbour will be unable to browse when my PC is down. I noticed yesterday when my PC was down, the subnet mask has changed from 255.255.255.0 to 255.0.0.0. We use DHCP and I have found am unused address so I'm using this static address on my box. It seems to be running better but I did have a lost connectivity this morning.
Our hardware:-
- Cisco Catalyst 4000 series switching hub, 10/100 auto sensing
- we do have a mix of cat 3 and cat 5 cabling (I am assume the hub will be able to isolate if a problem with a cable drop occur)
Thanks in advanced !
- ML
Thanks for your input. We have resolved it. This was due to a misconfiguration of our PIX firewall by our previous MIS manager (who was fired). Now, everything is working.
Regards,
-ML
------------
nethead at 10/31/00 2:23:58 PM
Things to think about and things to check.
The fact that you can ping ip addresses on your local subnet proves that your MAC layer 2 is working well. It seems that you are having the problem when you are at layer 3 sending packets across subnets using the default gateway. If your subnet mask is changing for some reason you will definately have some weird problems.
Are you getting DHCP services from your local DHCP server or from your ISP?
If it's your server, what is your lease time? Some DHCP servers/clients can have problems when the lease time is set to low (like a few hours). The fact that your subnet mask changed may indicate a DHCP problem, since the mask, default gateway and DNS server information is sent in the DHCP packet.
Something else to think about. Are you using the ip address or a host name in the ping command? Is your ISP providing DNS services for you? You may be having name resolution problems. Maybe caused by a DHCP problem or a DNS server problem.
Sure sounds like a DHCP problem of some sort. Try a release and renew command before you reboot next time. Command is winipcfg /release_all winipcfg /renew_all.
Good Luck
nethead
------------
ML at 8/25/00 12:24:49 PM
I am having a weird TCPIP problem which I would need some input:-
We have a TCPIP LAN (just one subnet) and a firewallgateway to the internet. We use win98 as client computers. Ocasionally, the win98 clients will be unable to get to the internet. When this happens, I can ping any internal addresses and the default gateway. However, I can't ping anywhere outside. At first, I though our ISP is down but when I checked my neighbour, he was fine with browsing the internet. So I rebooted my 98 box and it comes right back. It works fine for a random time (couple of hours/couple of days) and same thing happens again. Reboot will usually fix it for a while.
If my TCPIP stack is bad, then I should not be able to ping internally. If ISP is bad, then my neighbour will be unable to browse when my PC is down. I noticed yesterday when my PC was down, the subnet mask has changed from 255.255.255.0 to 255.0.0.0. We use DHCP and I have found am unused address so I'm using this static address on my box. It seems to be running better but I did have a lost connectivity this morning.
Our hardware:-
- Cisco Catalyst 4000 series switching hub, 10/100 auto sensing
- we do have a mix of cat 3 and cat 5 cabling (I am assume the hub will be able to isolate if a problem with a cable drop occur)
Thanks in advanced !
- ML
all yer kabelle should B at leazst kat 5. the cisco device you say you have is a switch....NOT a hub. i am assuming dat each computah haz it'z own switch port...resulsting in seperate collizion domainz.....which meenz ddat (if yer nick'z suppport it...) you can/should be running full duplex.
btw...windowz suckz fer dat
------------
ML at 8/25/00 12:24:49 PM
I am having a weird TCPIP problem which I would need some input:-
We have a TCPIP LAN (just one subnet) and a firewallgateway to the internet. We use win98 as client computers. Ocasionally, the win98 clients will be unable to get to the internet. When this happens, I can ping any internal addresses and the default gateway. However, I can't ping anywhere outside. At first, I though our ISP is down but when I checked my neighbour, he was fine with browsing the internet. So I rebooted my 98 box and it comes right back. It works fine for a random time (couple of hours/couple of days) and same thing happens again. Reboot will usually fix it for a while.
If my TCPIP stack is bad, then I should not be able to ping internally. If ISP is bad, then my neighbour will be unable to browse when my PC is down. I noticed yesterday when my PC was down, the subnet mask has changed from 255.255.255.0 to 255.0.0.0. We use DHCP and I have found am unused address so I'm using this static address on my box. It seems to be running better but I did have a lost connectivity this morning.
Our hardware:-
- Cisco Catalyst 4000 series switching hub, 10/100 auto sensing
- we do have a mix of cat 3 and cat 5 cabling (I am assume the hub will be able to isolate if a problem with a cable drop occur)
Thanks in advanced !
- ML
mizsta_know_nuttin
11-05-2000, 08:42 PM
all yer kabelle should B at leazst kat 5. the cisco device you say you have is a switch....NOT a hub. i am assuming dat each computah haz it'z own switch port...resulsting in seperate collizion domainz.....which meenz ddat (if yer nick'z suppport it...) you can/should be running full duplex.
btw...windowz suckz fer dat
------------
ML at 8/25/00 12:24:49 PM
I am having a weird TCPIP problem which I would need some input:-
We have a TCPIP LAN (just one subnet) and a firewallgateway to the internet. We use win98 as client computers. Ocasionally, the win98 clients will be unable to get to the internet. When this happens, I can ping any internal addresses and the default gateway. However, I can't ping anywhere outside. At first, I though our ISP is down but when I checked my neighbour, he was fine with browsing the internet. So I rebooted my 98 box and it comes right back. It works fine for a random time (couple of hours/couple of days) and same thing happens again. Reboot will usually fix it for a while.
If my TCPIP stack is bad, then I should not be able to ping internally. If ISP is bad, then my neighbour will be unable to browse when my PC is down. I noticed yesterday when my PC was down, the subnet mask has changed from 255.255.255.0 to 255.0.0.0. We use DHCP and I have found am unused address so I'm using this static address on my box. It seems to be running better but I did have a lost connectivity this morning.
Our hardware:-
- Cisco Catalyst 4000 series switching hub, 10/100 auto sensing
- we do have a mix of cat 3 and cat 5 cabling (I am assume the hub will be able to isolate if a problem with a cable drop occur)
Thanks in advanced !
- ML
mizsta_know_nuttin
11-05-2000, 08:42 PM
all yer kabelle should B at leazst kat 5. the cisco device you say you have is a switch....NOT a hub. i am assuming dat each computah haz it'z own switch port...resulsting in seperate collizion domainz.....which meenz ddat (if yer nick'z suppport it...) you can/should be running full duplex.
btw...windowz suckz fer dat
------------
ML at 8/25/00 12:24:49 PM
I am having a weird TCPIP problem which I would need some input:-
We have a TCPIP LAN (just one subnet) and a firewallgateway to the internet. We use win98 as client computers. Ocasionally, the win98 clients will be unable to get to the internet. When this happens, I can ping any internal addresses and the default gateway. However, I can't ping anywhere outside. At first, I though our ISP is down but when I checked my neighbour, he was fine with browsing the internet. So I rebooted my 98 box and it comes right back. It works fine for a random time (couple of hours/couple of days) and same thing happens again. Reboot will usually fix it for a while.
If my TCPIP stack is bad, then I should not be able to ping internally. If ISP is bad, then my neighbour will be unable to browse when my PC is down. I noticed yesterday when my PC was down, the subnet mask has changed from 255.255.255.0 to 255.0.0.0. We use DHCP and I have found am unused address so I'm using this static address on my box. It seems to be running better but I did have a lost connectivity this morning.
Our hardware:-
- Cisco Catalyst 4000 series switching hub, 10/100 auto sensing
- we do have a mix of cat 3 and cat 5 cabling (I am assume the hub will be able to isolate if a problem with a cable drop occur)
Thanks in advanced !
- ML
mizsta_know_nuttin
11-05-2000, 08:42 PM
all yer kabelle should B at leazst kat 5. the cisco device you say you have is a switch....NOT a hub. i am assuming dat each computah haz it'z own switch port...resulsting in seperate collizion domainz.....which meenz ddat (if yer nick'z suppport it...) you can/should be running full duplex.
btw...windowz suckz fer dat
------------
ML at 8/25/00 12:24:49 PM
I am having a weird TCPIP problem which I would need some input:-
We have a TCPIP LAN (just one subnet) and a firewallgateway to the internet. We use win98 as client computers. Ocasionally, the win98 clients will be unable to get to the internet. When this happens, I can ping any internal addresses and the default gateway. However, I can't ping anywhere outside. At first, I though our ISP is down but when I checked my neighbour, he was fine with browsing the internet. So I rebooted my 98 box and it comes right back. It works fine for a random time (couple of hours/couple of days) and same thing happens again. Reboot will usually fix it for a while.
If my TCPIP stack is bad, then I should not be able to ping internally. If ISP is bad, then my neighbour will be unable to browse when my PC is down. I noticed yesterday when my PC was down, the subnet mask has changed from 255.255.255.0 to 255.0.0.0. We use DHCP and I have found am unused address so I'm using this static address on my box. It seems to be running better but I did have a lost connectivity this morning.
Our hardware:-
- Cisco Catalyst 4000 series switching hub, 10/100 auto sensing
- we do have a mix of cat 3 and cat 5 cabling (I am assume the hub will be able to isolate if a problem with a cable drop occur)
Thanks in advanced !
- ML