DHCP offer wrong router

[Tangi]

Hello,
I have a public network with 3 sub-nets and associated gateways:
public3 XX.0/27 IPv4 XX.30
public XX.64/28 IPv4 XX.78
public2 XX.160/28 IPv4 XX.174

From time to time, I saw that on instantiated VM, the default route to the GW was missing.

Checking the DHCP answer, I noticed the proposed router was a wrong one.

We get the .174 instead of .78

see below DHCP offer :

    Bootstrap Protocol (ACK)
        Message type: Boot Reply (2)
        Hardware type: Ethernet (0x01)
        Hardware address length: 6
        Hops: 0
        Transaction ID: 0x70542239
        Seconds elapsed: 0
        Bootp flags: 0x0000 (Unicast)
            0... .... .... .... = Broadcast flag: Unicast
            .000 0000 0000 0000 = Reserved flags: 0x0000
        Client IP address: 0.0.0.0 (0.0.0.0)
        Your (client) IP address: XX.XX.XX.66 (XX.XX.XX.66)
        Next server IP address: XX.XX.XX.65 (XX.XX.XX.65)
        Relay agent IP address: 0.0.0.0 (0.0.0.0)
        Client MAC address: fa:16:3e:9c:ea:c4 (fa:16:3e:9c:ea:c4)
        Client hardware address padding: 00000000000000000000
        Server host name not given
        Boot file name not given
        Magic cookie: DHCP
        Option: (53) DHCP Message Type (ACK)
            Length: 1
            DHCP: ACK (5)
        Option: (54) DHCP Server Identifier
            Length: 4
            DHCP Server Identifier: XX.XX.XX.65 (XX.XX.XX.65)
        Option: (51) IP Address Lease Time
            Length: 4
            IP Address Lease Time: (86400s) 1 day
        Option: (58) Renewal Time Value
            Length: 4
            Renewal Time Value: (43200s) 12 hours
        Option: (59) Rebinding Time Value
            Length: 4
            Rebinding Time Value: (75600s) 21 hours
        Option: (1) Subnet Mask
            Length: 4
            Subnet Mask: 255.255.255.240 (255.255.255.240)
        Option: (28) Broadcast Address
            Length: 4
            Broadcast Address: XX.XX.XX.79 (XX.XX.XX.79)
        Option: (15) Domain Name
            Length: 14
            Domain Name: openstacklocal
        Option: (12) Host Name
            Length: 18
            Host Name: host-XX-XX-XX-66
        Option: (3) Router
            Length: 4
            Router: XX.XX.XX.174 (XX.XX.XX.174)
        Option: (121) Classless Static Route
            Length: 32
            Subnet/MaskWidth-Router: 169.254.169.254/32-XX.XX.XX.161
            Subnet/MaskWidth-Router: XX.XX.XX.0/27-0.0.0.0
            Subnet/MaskWidth-Router: XX.XX.XX.64/28-0.0.0.0
            Subnet/MaskWidth-Router: default-XX.XX.XX.174
        Option: (6) Domain Name Server
            Length: 8
            Domain Name Server: XX
            Domain Name Server: XX
        Option: (255) End
            Option End: 255

Could that it be an issue related to multiples sub-nets?

[Rodolfo Alonso (rodolfo-alonso-hernandez)]

Bug closed due to lack of activity, please feel free to reopen if needed.