Re: network unreachable
Leland Weathers <leland-Aw/i/[email protected]> Wed, 03 May 2006 07:14:25 -0500
| Newsgroups | gmane.org.user-groups.aclug.linux-help |
|---|---|
| Message-ID | <[email protected]> |
Leland Weathers wrote: Tom Hull wrote: Jeff Vian wrote: On Tue, 2006-05-02 at 01:41 -0500, Tom Hull wrote: Just on the off chance, and to rule out one other problem. Have you tried a different network cable? Have you tried a different port on the switch? yes. yes. tried booting ubuntu live disc. network still unreachable. iptables -L -n shows all rule sets as ACCEPT, which I take to mean no firewalling. You could verify the no "firewalling" by either doing a tcpdump on the interface when you do a ping. Or you could also ignore that statement since I did not take into consideration the Ubuntu livecd, which I know does not have that kind of firewall ruleset in place dmesg shows entries like: NETDEV WATCHDOG: eth0: transmit timed out eth0: no IPv6 routers present kernel 2.6.12; driver for eth0 is forcedeth.c 0.41 You can (at least in Fedora) use ethtool to look at and change settings on an adapter. Pre-FC5 I think it was miitool that did similar things. not easy to copy the output, but ethtool's basic output looks not unreasonable (omitting a couple of lines): Supported ports: [ MII ] Supports auto-negotiation: yes Advertised auto-negotiation: yes Speed: 100Mb/s Duplex: half Port: MII PHYAD:1 Transceiver: externel Auto-negotiation: on Supports Wake-on: g Wake-on: d Link detected: yes netstat -r reports MSS = 0; don't know whether that means no maximum segment size or 0, which could choke it; my Red Hat machines use 40. got a chassis intrusion message first time I rebooted after problem; reset and message went away; would be weird if BIOS disabled ethernet because of the chassis instrusion detect. I have a problem on a recently built Ubuntu Linux system. Sometime in the last day or two the machine lost its network connection. Ethernet controller is on the motherboard. It is configured with a static address, and can ping that address but nothing else on the local network. Changing cable and/or port on the otherwise working switch has no effect. We had some trouble yesterday when my gateway machine couldn't get a DHCP address from Cox for a period of several hours. Not sure whether the Ubuntu machine problem occurred at that time, since I didn't notice it until much later. I've rebooted since then. Don't see anything obviously wrong, e.g. in netstat -r or iptables -L. Aside from hardware, is there anything you can think of that might cause a Linux machine to effectively disconnect itself from a local network? Thanks. -- This is the [email protected] list. To unsubscribe, visit http://www.complete.org/cgi-bin/listargate-aclug.cgi