[Samba] excessive TCP retransmissions with samba 3.0, slow file
jeremy at angelar.com
Fri May 20 02:53:34 GMT 2005
Jeremy Anderson wrote:
> Hello all!
> I've got a Fedora Core 3 box running Samba 3.0.8.
> It serves a variety of roles, including mail server and samba server.
> The mail server is quite fast, but the smb server generates lots
> and lots of TCP retransmissions (as seen in ethereal). The general
> consensus is that this is new in the last few weeks. One user has
> been reporting speed problems for some time, but no metrics were ever
> I've tried replacing the NIC, but the problem follows. This is a
> small network, with two 100mbit hubs, and windows 2000 on all the
> I want to suspect hardware, but flood pings from a linux box
> put on the network never report dropped packets.
> All hosts are listed in DNS, and reverse DNS lookup is
> successful. I've also configured samba to pass WINS
> requests on to DNS.
> I'm absolutely stumped. I don't see the retransmissions
> with anything on the network except SMB-related TCP traffic.
> I don't see anything peculiar in /var/log/messages or the
> smbd.log file. nmbd is running just fine.
> Any assistance is greatly, greatly appreciated.
I'd like to thank everyone for the help with this problem. Replacing
the two Ethernet hubs with a single Ethernet switch seems to have
resolved the problem. The two hubs were actually hot to the touch
when I looked at them. I wouldn't have guessed that hardware would
affect just a single protocol, but it looks like only SMB was
chatty enough to overload the failing hubs.
Jeremy Anderson jeremy (at) angelar.com
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