Archive for November, 2008

Broadcom problems under linux

Thursday, November 20th, 2008

I’ve been trying to install Fedora 9 on a Dell PowerEdge T100 and have been tearing my hair out trying to get the network card to work.

The card in question is a Broadcom Netextreme BCM5722 Gigabit Ethernet PCI Express adapter.  I’ve used similar Broadcom cards in other machines without any problems, but this time around it didn’t want to play nicely.

Since I was doing an NFS install I couldn’t really do anything until this worked, but trying either a DHCP or a static configuration failed.

From a static configuration the error I got was:

result of pumpSetupInterface is pumpSetupInterface failed: create route - 1:Operation not permitted

From a DHCP configuration it was:

DHCPv4 eth0 - TIMED OUT

All the other messages about the card seemed OK.  The tg3 driver recognised it and even got as far as setting up the link and declaring it ready:

tg3: eth0: Link is up at 100Mbps, half duplex
tg3: eth0: Flow control is off for TX and off for RX
ADDRCONF (NETDEV_CHANGE) eth0: link becomes ready

After much tinkering I found that if I booted the machine with the ethernet cable disconnected and then only connected it once the card was trying to obtain an address everything suddently started working.  If the cable was connected from the start then the interface would never come up.  This provided me with enough of a work round to get Fedora 9 installed and updated.

Fortunately it seems the problem with this card and the tg3 driver has been fixed between the initial fedora 9 release kernel and the current update kernel (2.6.27.5-37.fc9.x86_64), such that after updating I was able to reboot without having to disconnect the ethernet cable and everthing still worked.

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Troubleshooting IMAP SSL

Wednesday, November 5th, 2008

I’ve just spent a while trying to troubleshoot my SSL IMAP connection.  This is the first time I’ve had to do any diagnostics since switching to an SSL secured mail connection.

When my connection stopped working I got only a very non-specific error from OSX mail, and no error at all from Thunderbird (it just hung).  If I was using an unsecured connection I’d usually try to check the connection manually using telnet, but trying this against the SSL port on my IMAP server didn’t get any response.

Having done some digging I found that you can test an SSL secured connection using the tools included with openssh.  In the case of IMAP you can connect to the server using:

openssl s_client -connect mail.example.com:993

In my case this failed (hence things not working!), with the error:

CONNECTED(00000003)
write:errno=54

Reading through the openssl documentation I found that this error usually results from the connection not being able to auto-negotiate a suitable ssl version to use.  If this is the case you can force a specific ssl version using:

openssl s_client -connect mail.example:993 -ssl2

or

openssl s_client -connect mail.example.com:993 -ssl3

If you want more information you can also add -debug to the command to see a full list of the commands being sent and a hex dump translation.

In my case I found that the connection only worked when sslv3 was forced, forcing sslv2 or allowing the connection to autonegotiate caused the connection to fail.  Since none of the mail clients I could find allow you to force a specific ssl version my email wouldn’t work.

Fortunately my hosting provider Orchard Hosting were very quick to respond when I reported this and have fixed things.

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