RE: ADSL problems with 10/100 NICs
Unlike a 10/100 hub a switch will not automatically handle differences in communication speeds. I never used 3com switches but they all have one thing in common - the direct cable connection, some even a telnet connection. All you have to do is enter the interface and configure the switch, I belive that bye seperating the switch into "semi-subnets" you will solve the problem. for example, lets say its a 16 port switch, just make the first 8 10MBit and the last 8 100MBit, the switch then will use logic to transfer packets between the two "subnets". another thing you should do while inside the interface is check the port status, i belive you should see many collisions and packet timeouts which were caused by the missconfiguration of the switch and they are the reason your sessions broke up. -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Aviram Jenik Sent: Thursday, June 07, 2001 8:48 AM To: Shaul Karl Cc: linux ILUG Subject: Re: ADSL problems with 10/100 NICs > > My guess is that those machines are sending packets in 100mbps whereas the > > Linux machine uses a 10mbps card and loses packets, which results in a > > broken connection. > > I was under the impression that a good dual-speed switch should handle those speed differences by itself, transparently. What is the model of your switch? > Yes, I thought so too. Note that network communication is working, but occasionally web pages are not displayed and e-mail download gets broken. The switch is a 3COM OfficeConnect Dual speed switch. - Aviram = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED] = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
RE: ADSL problems with 10/100 NICs
Hello, I'm certainly NOT a network expert but I'm working right now on network with mixed 100 and 10 mbps stations, connected with a switch and I don't see any problem in such setup. IMHO any decent switch should be able to handle speed differences. At home I had a similar problem which turned out to be wrong MTU. So I suggest you check the ADSL Howto and verify that you have lowered MTU on all workstations or implemented the iptables fix if you have 2.4 kernel. Haim. > -Original Message- > From: [EMAIL PROTECTED] > [mailto:[EMAIL PROTECTED]]On Behalf Of fredy > Sent: Thursday, June 07, 2001 1:02 PM > To: Aviram Jenik; Shaul Karl > Cc: linux ILUG > Subject: RE: ADSL problems with 10/100 NICs > > > Unlike a 10/100 hub a switch will not automatically handle > differences in > communication speeds. > I never used 3com switches but they all have one thing in > common - the > direct cable connection, some even a telnet connection. > All you have to do is enter the interface and configure the > switch, I belive > that bye seperating the switch into "semi-subnets" you will > solve the > problem. > for example, lets say its a 16 port switch, just make the > first 8 10MBit and > the last 8 100MBit, the switch then will use logic to > transfer packets > between the two "subnets". > another thing you should do while inside the interface is > check the port > status, i belive you should see many collisions and packet > timeouts which > were caused by the missconfiguration of the switch and they > are the reason > your sessions broke up. > > -Original Message- > From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Aviram Jenik Sent: Thursday, June 07, 2001 8:48 AM To: Shaul Karl Cc: linux ILUG Subject: Re: ADSL problems with 10/100 NICs > > My guess is that those machines are sending packets in 100mbps whereas the > > Linux machine uses a 10mbps card and loses packets, which results in a > > broken connection. > > I was under the impression that a good dual-speed switch should handle those speed differences by itself, transparently. What is the model of your switch? > Yes, I thought so too. Note that network communication is working, but occasionally web pages are not displayed and e-mail download gets broken. The switch is a 3COM OfficeConnect Dual speed switch. - Aviram = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED] = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED] = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: ADSL problems with 10/100 NICs
Hi, > At home I had a similar > problem which turned out to be wrong MTU. So I suggest you check the > ADSL Howto and verify that you have lowered MTU on all workstations or > implemented the iptables fix if you have 2.4 kernel. > Seems strange to me that the problem would be MTU related, since the same workstation works if I put a 10mb card instead of the 100. Also, it doesn't explain the fact the problem suddenly appeared when I replaced the hub with a switch. - Aviram = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: ADSL problems with 10/100 NICs
Hi, I dont know exactly but from my experience the problem should be a misconfiguration in your switch. At 18:06 07/06/01 +0200, you wrote: >Hi, > > > At home I had a similar > > problem which turned out to be wrong MTU. So I suggest you check the > > ADSL Howto and verify that you have lowered MTU on all workstations or > > implemented the iptables fix if you have 2.4 kernel. > > >Seems strange to me that the problem would be MTU related, since the same >workstation works if I put a 10mb card instead of the 100. Also, it doesn't >explain the fact the problem suddenly appeared when I replaced the hub with >a switch. > >- Aviram > > >= >To unsubscribe, send mail to [EMAIL PROTECTED] with >the word "unsubscribe" in the message body, e.g., run the command >echo unsubscribe | mail [EMAIL PROTECTED] Regards, Eran Levy. E-mail: [EMAIL PROTECTED] WebSite: http://www15.brinkster.com/liloboot = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: ADSL problems with 10/100 NICs
> Hi, > I dont know exactly but from my experience the problem should be a > misconfiguration in your switch. Yes, that sounds like it. There doesn't seem to be a way to configure the switch, though. - Aviram = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
RE: ADSL problems with 10/100 NICs
Check the switch in the back (or front...i dont know what your switch looks like) it should have at least a serial connection, its the direct cable connection. altough some have a RJ45 conection for direct cable. like i said, just tap into it and check what's the current config. is it a used switch? did someone configure it before you? -Original Message- From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED]]On Behalf Of Aviram Jenik Sent: Thursday, June 07, 2001 8:22 PM To: [EMAIL PROTECTED]; Eran Levy Subject: Re: ADSL problems with 10/100 NICs > Hi, > I dont know exactly but from my experience the problem should be a > misconfiguration in your switch. Yes, that sounds like it. There doesn't seem to be a way to configure the switch, though. - Aviram = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED] = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
Re: ADSL problems with 10/100 NICs
On Wed, 6 Jun 2001, Aviram Jenik wrote: > I'm having a strange problem with my ADSL connection. I'm not sure the > problem is Linux related (probably isn't), but hopefully the solution is > Linux related :-) > > I recently replaced my home network's hub with a dual-speed switch (3Com's > officeconnect) that supports both 10 and 100 connections. > My home network has a mix of 10 and 100 NICs, where the Linux machine that > serves as my ADSL gateway has a 10mb NIC, but 2 Windows machines on the > network have 100mb NICs. > Since the upgrade, those two machines suffer from strange problems while > surfing the web and downloading e-mails, where the connection is sometimes > terminated abruptly. > My guess is that those machines are sending packets in 100mbps whereas the > Linux machine uses a 10mbps card and loses packets, which results in a > broken connection. > Installing a 10mbps card on one of these stations solved the problem, but > obviously that isn't the solution I'm looking for. > Is there any way I can configure either the Linux gateway or the Windows > machines to solve this problem (MTU settings perhaps?!). Check for duplex settings mismatch. This is the most common problem we had with 3Com switches (and switches in general). Although this usually causes slow tranfer rates rather than broken connections. Do notice that some NICs do not let you set the card's speed and duplex (SGI and some Sun models). In this case disabling duplex auto negotiate and forcing full duplex on the port is a sure way of causing duplex mismatch because these NICs will fall back to half duplex. Also, but this is extremely unlikely, you might have some compatibility problems. I've seen a 3Com LS1100 which had similar problems with Accton NICs of a very specific vintage (November '99 if I am recalling correctly). Also, I have seen some problems with Kingston's hubs. Replace the 100Mb cards with other brands (Intel EtherExpress is always a good choise). > > TIA. > > - Aviram > > > > > = > To unsubscribe, send mail to [EMAIL PROTECTED] with > the word "unsubscribe" in the message body, e.g., run the command > echo unsubscribe | mail [EMAIL PROTECTED] > > -- Yaron. = To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
