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Hi Mike, re: > OK, as far as duplexing; does that mean we need half duplex instead of what > I show here? No, you want full duplex. re: > [mapm3@vulcan ~]$ dmesg | grep -i duplex > [ 8.087990] bnxt_en 0000:19:00.0 eth2: NIC Link is Up, 1000 Mbps full > duplex, Flow control: none > > [mapm3@charney ~]$ dmesg | grep -i duplex > [ 23.260052] e1000e: eth0 NIC Link is Up 1000 Mbps Full Duplex, Flow > Control: None This was the setup on boot. You can use 'ethtool' to check what the interface is running at now. For instance: <as 'root' on vulcan> ethtool eth2 The output will show what is supported, and what is current. Here is the output from one of our machines as an example of what your output might look like: [root@lead ~]# ethtool eth0 Settings for eth0: Supported ports: [ TP ] Supported link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Supported pause frame use: Symmetric Supports auto-negotiation: Yes Advertised link modes: 10baseT/Half 10baseT/Full 100baseT/Half 100baseT/Full 1000baseT/Full Advertised pause frame use: Symmetric Advertised auto-negotiation: Yes Speed: 1000Mb/s Duplex: Full Port: Twisted Pair PHYAD: 1 Transceiver: internal Auto-negotiation: on MDI-X: off (auto) Supports Wake-on: pumbg Wake-on: g Current message level: 0x00000007 (7) drv probe link Link detected: yes You will see from this listing that 3 modes are supported (10, 100 and 1000) and the interface is running at 1000 (1 Gbps) using full duplex. re: > Also, as a test I changed the charney SATELLITE feed to iddc. And as a > reminder charney is doing nothing except receiving the CONUS and FullDisk. I haven't forgotton. re: > The fact that I start with a new clean slate queue and data still just > trickles in is troubling and just confirms the suspected shaping, true? Yes, I'd say that this is definitive. I brought up the other tests so completely eliminate other possibilities. What other possibilities you may ask? We have see the Ethernet interface on one of our machines auto-renegotiate to a speed lower than the maximum that is supported, 100 as opposed to 1000. When that happened, the flow of data into the machine turned from a torrent to a trickle. Ethtool can be used to tell the interface to re-auto-negotiate, and after doing that, our connection returned to 1000 Mbps. As I said during our phone conversation: there are LOTS of things going on, so checking them all out is a bit arduous. We have found, however, that we have had to jump through major hoops before the network folks at institutions that we were trying to help would even feign to believe that there was something in their network that was causing a problem :-( Cheers, Tom -- **************************************************************************** Unidata User Support UCAR Unidata Program (303) 497-8642 P.O. Box 3000 address@hidden Boulder, CO 80307 ---------------------------------------------------------------------------- Unidata HomePage http://www.unidata.ucar.edu **************************************************************************** Ticket Details =================== Ticket ID: AFT-567406 Department: Support LDM Priority: Normal Status: Open =================== NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.