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• Where is the main docker config (yaml file)?
• Why, with rx-gro-hw=off on naasc-vs-4, does na-arc-6 see so many retransmissions and small Congestion Window (Cwnd)?

  • [root@na-arc-6 ~]# iperf3 -B 10.0.0.16 -c 10.0.0.21
    Connecting to host 10.0.0.21, port 5201
    [  4] local 10.0.0.16 port 38534 connected to 10.0.0.21 port 5201
    [ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
    [  4]   0.00-1.00   sec   302 MBytes  2.54 Gbits/sec  523    207 KBytes

          

    
    [  4]   1.00-2.00   sec   322 MBytes  2.70 Gbits/sec  596    186 KBytes

          

    
    [  4]   2.00-3.00   sec   312 MBytes  2.62 Gbits/sec  687    245

    KBytes       

     KBytes
    
    

  • [root@na-arc-3 ~]# iperf3 -B 10.0.0.19 -c 10.0.0.21
    Connecting to host 10.0.0.21, port 5201
    [  4] local 10.0.0.19 port 52986 connected to 10.0.0.21 port 5201
    [ ID] Interval           Transfer     Bandwidth       Retr  Cwnd
    [  4]   0.00-1.00   sec   309 MBytes  2.59 Gbits/sec  232    638 KBytes
    [  4]   1.00-2.00   sec   358 MBytes  3.00 Gbits/sec    0    967 KBytes
    [  4]   2.00-3.00   sec   351 MBytes  2.95 Gbits/sec    0   1.18 MBytes 
    [  4]   3.00-4.00   sec   339 MBytes  2.84 Gbits/sec   74   1.36 MBytes
    [  4]   4.00-5.00   sec   359 MBytes  3.01 Gbits/sec    0   1.54 MBytes
    
    

• Why does naasc-vs-3 have a br120 in state UNKNOWN?  none of the other naasc-vs nodes have a br120.
• Why does naasc-vs-4 have all the infiniband modules loaded?  I don't see an IB card.  naasc-vs-1 and naasc-dev-vs also have some IB modules loaded but naasc-vs-3 and naasc-vs-5 don't have any IB modules loaded.
  • Tracy will look into this
• Why is nfnetlink logging enabled on naasc-vs-4?  You can see this with cat /proc/net/netfilter/nf_log and lsmod|grep -i nfnet
  • nfnetlink is a module for packet mangling.  Could this interfear with the docker swarm networking?
• why is the eth1 interfaces in all the containers and docker_gwbridge on na-arc-1 in the 172.18.x.x range while all the other na-arcs are in the 172.19.x.x range?  Does it matter?
• Here are some diffs in sysctl on na-arc nodes.  I tried changed na-arc-4 and na-arc-5 to match the others but performance was the same.  I then changed all the nodes to match na-arc-{1..3} and still no change in performance.  I still don't understand how na-arc-{4..5} got different setttings.  I did find that there is another directory for sysctl settings in /usr/lib/sysctl.d but that isn't why these are different.
  
  • na-arc-1, na-arc-2, na-arc-3, natest-arc-1, natest-arc-2, natest-arc-3
    

    • net.bridge.bridge-nf-call-arptables = 0

      net.bridge.bridge-nf-call-ip6tables = 0

      net.bridge.bridge-nf-call-iptables = 1

  • na-arc-4, na-arc-5

    • net.bridge.bridge-nf-call-arptables = 1

      net.bridge.bridge-nf-call-ip6tables = 1

      net.bridge.bridge-nf-call-iptables = 1

• I see sysctl differences between the natest-arc servers and the na-arc servers.  Here is a diff of /etc/sysctl.d/99-nrao.conf on natest-arc-1 and na-arc-5
  

  • < #net.ipv4.tcp_tw_recycle = 1
    ---
    > net.ipv4.tcp_tw_recycle = 1
    22,39d21
    < net.ipv4.conf.all.accept_redirects=0
    < net.ipv4.conf.default.accept_redirects=0
    < net.ipv4.conf.all.secure_redirects=0
    < net.ipv4.conf.default.secure_redirects=0
    <
    < #net.ipv6.conf.all.disable_ipv6 = 1
    < #net.ipv6.conf.default.disable_ipv6 = 1
    <
    < # Mellanox recommends the following
    < net.ipv4.tcp_timestamps = 0
    < net.core.netdev_max_backlog = 250000
    <
    < net.core.rmem_default = 16777216
    < net.core.wmem_default = 16777216
    < net.core.optmem_max = 16777216
    < net.ipv4.tcp_mem = 16777216 16777216 16777216
    < net.ipv4.tcp_low_latency = 1

  • If I set net.ipv4.tcp_timestamps = 0 on na-arc-5, the wget download drops to nothing (--.-KB/s).

  • If I set all the above sysctl options, execpt net.ipv4.tcp_timestamps, on all five na-arc nodes, wget download performance doesn't change.  It is still about 32KB/s.  Also I still zeeo ZeroWindow packets.
  • Try rebooting VMs after making changes?
• I see ZeroWindow packets sent from na-arc-5 to nangas13 while downloading a file from nangas13 using wget.  This is na-arc-5 telling nangas13 to wiat because its network buffer is full.
  • Is this because of qdisc pfifo_fast?  No.  krowe changed eth0 to *qdisc fq_codel* and still seeing ZeroWait packets.
  • Now that I have moved the rh_download to na-arc-1 and put httpd on na-arc-5 I no longer see ZeroWindow packets on na-arc-5.  But I am seeing them on na-arc-1 which is where the rh_downloader is now.  Is this because the rh_downloader is being stalled talking to something else like httpd and therefore telling nangas13 to wait?
• Why does almaportal use ens3 while almascience uses eth0?
• What if we move the rh-downloader container to a different node?  In fact walk it through all five nodes and test.
• Why do I see cv-6509 when tracerouting from na-arc-5 to nangas13 but not on natest-arc-1

  • [root@na-arc-5 ~]# traceroute nangas13
    traceroute to nangas13 (10.2.140.33), 30 hops max, 60 byte packets
     1  cv-6509-vlan97.cv.nrao.edu (10.2.97.1)  0.426 ms  0.465 ms  0.523 ms
     2  cv-6509.cv.nrao.edu (10.2.254.5)  0.297 ms  0.277 ms  0.266 ms
     3  nangas13.cv.nrao.edu (10.2.140.33)  0.197 ms  0.144 ms  0.109 ms

     

  • [root@natest-arc-1 ~]# traceroute nangas13
    traceroute to nangas13 (10.2.140.33), 30 hops max, 60 byte packets
     1  cv-6509-vlan96.cv.nrao.edu (10.2.96.1)  0.459 ms  0.427 ms  0.402 ms
     2  nangas13.cv.nrao.edu (10.2.140.33)  0.184 ms  0.336 ms  0.311 ms

  • Derek wrote that 10.2.99.1 = CV-NEXUS and 10.2.96.1 = CV-6509
• Why does natest-arc-3 have ens3 instead of eth0 and why is its speed 100Mb/s?
  • virsh domiflist natest-arc-3 shows the Model as rtl8139 instead of virtio
  • When I run ethtool eth0 on nar-arc-{1..5} natest-arc-{1..2} as root, the result is just Link detected: yes instead of the full report with speed while na-arc-3 shows 100Mb/s.
• Why do iperf tests from natest-arc-1 and natest-arc-2 to natest-arc-3 get about half the performance (0.5Gb/s) expected especially when the reverse tests get expected performance (0.9Gb/s).
• Is putting the production swarm nodes (na-arc-*) on the 10Gb/s network a good idea?  Sure it makes a fast connection to cvsan but it adds one more hop to the nangas servers (e.g. na-arc-1 -> cv-nexus9k -> cv-nexus -> nangas11)
• When I connect to the container acralmaprod001.azurecr.io/offline-production/rh-download:2022.06.01.2022jun I get errors like unknown user 1009  I get the same errors on the natest-arc-1 container.
• Does it matter that the na-arc nodes are on 10.2.97.x, their VM host is on 10.2.99.x while the natest-arc nodes are on 10.2.96.x and their VM hosts (well 2 out of 3) are also on 10.2.96.x?  Is this why I see cv-509.cv.nrao.edu when running traceroute from the na-arc nodes?
• When running wget --no-check-certificate http://na-arc-3.cv.nrao.edu:8088/dataPortal/member.uid___A001_X1358_Xd2.3C286_sci.spw31.cube.I.pbcor.fits I see traffic going through veth14ce034 on na-arc-3 but I can't find a container associated with that veth.
• Why does the httpd container have eth0(10.0.0.8).  This is the ingress network.  I don't see any other conrainter with an interface on 10.0.0.0/24.
• Do we want to use jumbo frames?  If so, some recommend using mtu=8900 and there are a lot of places it needs to be set.
  • https://vswitchzero.com/2018/08/02/jumbo-frames-and-vxlan-performance/
  • https://docs.docker.com/engine/swarm/networking/

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