topic ifconfig command and network hangs in Operating System - HP-UX

ifconfig command and network hangs

Barry Feinberg — Wed, 19 Mar 2003 15:10:57 GMT

I am trying to configure a lan card using ifconfig "land6 10.128.44.52 netmask 255.0.0.0" and the command / network hangs. I have to unplumb lan6 from the console to unhang network. When I try to configure from sam I get the warning. "CAUTION: There is already an entry for the system name in the host table. netstat -i shows no entrie nor dose /etc/hosts or arp. What could the problem be?

Re: ifconfig command and network hangs

Ravi_8 — Wed, 19 Mar 2003 15:20:06 GMT

Hi,

did you tried using lanadmin?

Re: ifconfig command and network hangs

Barry Feinberg — Wed, 19 Mar 2003 15:26:26 GMT

Lanadmin shows card ok.
PPA Number = 6
Description = lan6 HP A5230A/B5509BA PCI 10/100Base-TX Addon [100BASE-TX,HD,A
Type (value) = ethernet-csmacd(6)
MTU Size = 1500
Speed = 100000000
Station Address = 0x1083fb871e
Administration Status (value) = up(1)
Operation Status (value) = up(1)
Last Change = 464794437
Inbound Octets = 500615802
Inbound Unicast Packets = 4
Inbound Non-Unicast Packets = 2360377
Inbound Discards = 0
Inbound Errors = 0
Inbound Unknown Protocols = 2359354
Outbound Octets = 31542
Outbound Unicast Packets = 690
Outbound Non-Unicast Packets = 684
Outbound Discards = 0
Outbound Errors = 0
Outbound Queue Length = 0
Specific = 655367

Press to continue

Ethernet-like Statistics Group

Index = 7
Alignment Errors = 0
FCS Errors = 0
Single Collision Frames = 0
Multiple Collision Frames = 0
Deferred Transmissions = 0
Late Collisions = 0
Excessive Collisions = 0
Internal MAC Transmit Errors = 0
Carrier Sense Errors = 0
Frames Too Long = 0
Internal MAC Receive Errors = 0

Re: ifconfig command and network hangs

Ken Hubnik_2 — Wed, 19 Mar 2003 15:30:54 GMT

Review your /etc/rc.config.d/netconf file and make sure everything is right in there. There is an entry in it for hostname.

Re: ifconfig command and network hangs

Uday_S_Ankolekar — Wed, 19 Mar 2003 15:31:42 GMT

Check if the same IP address has been used in DNS server.

try nslookup ipaddress and see if it gets resolved somehow.

-USA..

Re: ifconfig command and network hangs

Ravi_8 — Wed, 19 Mar 2003 15:45:18 GMT

Hi,

could you move resolv.conf to something else and use ifconfig

(mv /etc/resolv.conf /etc/resolv.conf.old)

Re: ifconfig command and network hangs

Barry Feinberg — Wed, 19 Mar 2003 15:55:04 GMT

1. I tried ifconfig with and without an entry in netconf. It hangs my network either way.

2. Yes nslookup does show name.

3 I don't have an entry in /etc/resolv.conf for this IP so I don't think that could be an issue.

Re: ifconfig command and network hangs

Steven E. Protter — Wed, 19 Mar 2003 18:50:25 GMT

Barry, HP-UX will hang if you try and configure two NIC cards on the same subnet.

lets say lan0 is 192.168.0.2 255.255.255.0

ifconfig lan1 192.168.0.3 netmask 255.255.255.0

This will hang networking and drop the box right off the network.

It's a common error, since apparently you can get away with this in Linux.

Check that, check for duplicate IP addresses elsewhere on the network.

SEP

Re: ifconfig command and network hangs

Barry Feinberg — Wed, 19 Mar 2003 19:30:20 GMT

I tried different subnets and have the same problem. I'm looking into maybe another server having the same IP address.

Re: ifconfig command and network hangs

Jon Finley — Thu, 20 Mar 2003 05:25:18 GMT

If you duplicated your system disks from another system, check under /etc/rc.config.d within the HPETHERCONF file.

SAM appearently has a sense of humor in that it will burn the MAC address for the NIC's into this file if you use it to configure your cards. The system will then appear to have a duplicate IP address because of the duplicate MAC address on the network.

Remove the entries.

Jon

Re: ifconfig command and network hangs

Barry Feinberg — Thu, 20 Mar 2003 13:57:50 GMT

Steven was right after all. I was changing the submask but was changing the wrong segment in subnet. Steven gets the points.

Re: ifconfig command and network hangs

rick jones — Thu, 20 Mar 2003 18:20:06 GMT

Stephen -

It may seem a nit, but HP-UX networking _may_ _appear_ to hang if one configures multiple physical interfaces into the same subnet, and those interfaces are not connected to the same broadcast domain (switch fabric).

"Livelock" or somesuch may be a better term though - the stack is still sending and receiving packets, it is just that the packets it is sending may not reach the destination becaue they've gone out the one interface rather than the other(s).

Configuring multiple physical interfaces into the same subnet and getting things to work as typicaly desired is _possible_ but it requires some combination of specific host/net routes and/or use of ip_strong_es_model.