yahoo-eng-team team mailing list archive

[Lajos Katona <1598078@xxxxxxxxxxxxxxxxxx>]

As this bug is inactive for years I close it now, feel free to reopen it

** Changed in: neutron
       Status: New => Won't Fix

-- 
You received this bug notification because you are a member of Yahoo!
Engineering Team, which is subscribed to neutron.
https://bugs.launchpad.net/bugs/1598078

Title:
  dnsmasq replies are incorrect after multiple simultaneously reloads

Status in neutron:
  Won't Fix

Bug description:
  When boot lot of instances by single request (nova boot --min-count 90), some instances do not receive DHCP reply.
  After investigation found that DHCP server for some requests answers to correct address and for some requests answers to broadcast.

  Packages captured by tcpdump:
  13:37:44.298533 3c:fd:fe:9c:62:c4 > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800), length 590: (tos 0x0, ttl 20, id 0, offset 0, flags [none], proto UDP (17), length 576)
     0.0.0.0.68 > 255.255.255.255.67: [udp sum ok] BOOTP/DHCP, Request from 3c:fd:fe:9c:62:c4, length 548, xid 0xfe9c62c4, Flags [Broadcast] (0x8000)
        Client-Ethernet-Address 3c:fd:fe:9c:62:c4
        Vendor-rfc1048 Extensions
          Magic Cookie 0x63825363
          DHCP-Message Option 53, length 1: Discover
          Parameter-Request Option 55, length 36:
            Subnet-Mask, Time-Zone, Default-Gateway, Time-Server
            IEN-Name-Server, Domain-Name-Server, RL, Hostname
            BS, Domain-Name, SS, RP
            EP, RSZ, TTL, BR
            YD, YS, NTP, Vendor-Option
            Requested-IP, Lease-Time, Server-ID, RN
            RB, Vendor-Class, TFTP, BF
            Option 128, Option 129, Option 130, Option 131
            Option 132, Option 133, Option 134, Option 135
          MSZ Option 57, length 2: 1260
          GUID Option 97, length 17: 0.55.49.57.48.54.49.85.83.69.53.51.55.87.78.89.54
          ARCH Option 93, length 2: 0
          NDI Option 94, length 3: 1.2.1
          Vendor-Class Option 60, length 32: "PXEClient:Arch:00000:UNDI:002001"
          END Option 255, length 0
          PAD Option 0, length 0, occurs 200
  13:37:44.298819 fa:16:3e:f0:b1:23 > ff:ff:ff:ff:ff:ff, ethertype IPv4 (0x0800), length 401: (tos 0xc0, ttl 64, id 30122, offset 0, flags [none], proto UDP (17), length 387)
     10.51.1.1.67 > 255.255.255.255.68: [udp sum ok] BOOTP/DHCP, Reply, length 359, xid 0xfe9c62c4, Flags [Broadcast] (0x8000)
        Your-IP 10.51.5.125
        Server-IP 10.51.0.4
        Client-Ethernet-Address 3c:fd:fe:9c:62:c4
        Vendor-rfc1048 Extensions
          Magic Cookie 0x63825363
          DHCP-Message Option 53, length 1: Offer
          Server-ID Option 54, length 4: 10.51.1.1
          Lease-Time Option 51, length 4: 600
          RN Option 58, length 4: 300
          RB Option 59, length 4: 525
          Subnet-Mask Option 1, length 4: 255.255.0.0
          BR Option 28, length 4: 10.51.255.255
          Domain-Name Option 15, length 14: "openstacklocal"
          Hostname Option 12, length 16: "host-10-51-5-125"
          TFTP Option 66, length 10: "10.51.0.4^@"
          BF Option 67, length 11: "pxelinux.0^@"
          Default-Gateway Option 3, length

  After restart of neutron-dhcp-agent this issue gone.
  Looks like on bunch of port-create and port-update operations neutron-dhcp-agent sends HUP signal to dnsmasq for reload to frequently.
  dnsmasq do clear cache and read files by signal event asynchronously which causes errors in loaded data.

To manage notifications about this bug go to:
https://bugs.launchpad.net/neutron/+bug/1598078/+subscriptions