我們收到了 Hetzner 網路團隊的電子郵件，要求我們不要使用屬於該子網路的虛擬機器的 MAC 位址。
我們將Xen伺服器主機設定為路由器使用本指南。
在詢問更多詳細資訊後，Hetzner 支援人員回答說，通常情況下，虛擬機器管理程式的網路配置應該只允許封包使用真實 NIC 的 MAC 位址退出系統。但如果您沒有發現問題，您可以嘗試使用 IPtables 封鎖這些傳出資料包。
所以我們的問題是：
如果有人在 Hetzner 或其他專用伺服器供應商處遇到此類問題。
你是怎麼解決的？使用 iptables 進行阻止是唯一的方法嗎？
謝謝
配置詳情
主機/路由器設定：
[root@xenserver-custom ~]# cat /etc/sysctl.conf
net.ipv4.ip_forward = 1
net.ipv6.conf.all.forwarding=1
net.ipv4.conf.default.proxy_arp = 0
net.ipv4.conf.all.send_redirects = 0
net.ipv4.conf.default.send_redirects = 0
net.ipv4.conf.lo.send_redirects = 0
net.ipv4.conf.xenbr0.send_redirects = 0
[root@xenserver-custom network-scripts]# ip addr add 85.91.107.177/28 dev xenbr0
[root@xenserver-custom ~]# ifconfig
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
ether 0c:c4:7a:e7:dc:33 txqueuelen 1000 (Ethernet)
RX packets 4704816217 bytes 6002063739181 (5.4 TiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 6294828922 bytes 7643975899027 (6.9 TiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
lo: flags=73<UP,LOOPBACK,RUNNING> mtu 65536
inet 127.0.0.1 netmask 255.0.0.0
loop txqueuelen 1 (Local Loopback)
RX packets 518545683 bytes 6322784653872 (5.7 TiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 518545683 bytes 6322784653872 (5.7 TiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
vifxxxx
.....................
xenbr0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 1500
inet 115.35.61.184 netmask 255.255.255.192 broadcast 115.35.61.191
ether 0c:c4:7a:e7:dc:33 txqueuelen 1 (Ethernet)
RX packets 3070611738 bytes 8670969429554 (7.8 TiB)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 2680055664 bytes 9822630727363 (8.9 TiB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
[root@xenserver-enginatics1 sysconfig]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 65536 qdisc noqueue state UNKNOWN qlen 1
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc mq master ovs-system state UP qlen 1000
link/ether 0c:c4:7a:e7:dc:33 brd ff:ff:ff:ff:ff:ff
3: ovs-system: <BROADCAST,MULTICAST> mtu 1500 qdisc noop state DOWN qlen 1
link/ether 72:ab:90:89:cf:cb brd ff:ff:ff:ff:ff:ff
4: xenbr0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc noqueue state UNKNOWN qlen 1
link/ether 0c:c4:7a:e7:dc:33 brd ff:ff:ff:ff:ff:ff
inet 115.35.61.184/26 brd 115.35.61.191 scope global dynamic xenbr0
valid_lft 37373sec preferred_lft 37373sec
inet 85.91.107.177/28 scope global xenbr0
valid_lft forever preferred_lft forever
31: vif15.0: <BROADCAST,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc mq master ovs-system state UP qlen 32
link/ether fe:ff:ff:ff:ff:ff brd ff:ff:ff:ff:ff:ff
44: vif21.0: <BROADCAST,MULTICAST,NOARP,UP,LOWER_UP> mtu 1500 qdisc mq master ovs-system state UP qlen 32
link/ether fe:ff:ff:ff:ff:ff brd ff:ff:ff:ff:ff:ff
..........
VM 來賓配置
[root@r1213a network-scripts]# cat /etc/sysconfig/network-scripts/ifcfg-eth0
DEVICE=eth0
TYPE=Ethernet
ONBOOT=yes
NM_CONTROLLED=yes
BOOTPROTO=static
IPADDR=85.91.107.184
PREFIX=28
GATEWAY=85.91.107.177
DNS1=213.133.98.98
DEFROUTE=yes
IPV4_FAILURE_FATAL=yes
IPV6INIT=no
[root@r1213a network-scripts]# ifconfig
eth0 Link encap:Ethernet HWaddr B6:8F:14:74:A6:B6
inet addr:85.91.107.184 Bcast:85.91.107.191 Mask:255.255.255.240
inet6 addr: fe80::b48f:14ff:fe74:a6b6/64 Scope:Link
UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1
RX packets:27122939 errors:0 dropped:2 overruns:0 frame:0
TX packets:2218911 errors:0 dropped:0 overruns:0 carrier:0
collisions:0 txqueuelen:1000
RX bytes:5404322465 (5.0 GiB) TX bytes:1061055301 (1011.9 MiB)
[root@r1213a ~]# ip addr
1: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue state UNKNOWN
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether b6:8f:14:74:a6:b6 brd ff:ff:ff:ff:ff:ff
inet 85.91.107.184/28 brd 85.91.107.191 scope global eth0
inet6 fe80::b48f:14ff:fe74:a6b6/64 scope link
valid_lft forever preferred_lft forever
[root@r1213a network-scripts]# ip route
default via 85.91.107.177 dev eth0
85.91.107.176/28 dev eth0 proto kernel scope link src 85.91.107.184
[root@r1213a network-scripts]# traceroute google.com
traceroute to google.com (172.217.18.110), 30 hops max, 60 byte packets
1 xenserver.localdomain (85.91.107.177) 0.081 ms 0.029 ms 0.039 ms
2 static.129.61.69.159.clients.your-server.de (159.69.61.129) 0.390 ms 0.410 ms 0.370 ms
3 core22.fsn1.hetzner.com (213.239.245.121) 0.393 ms 0.416 ms 0.424 ms
4 core0.fra.hetzner.com (213.239.252.33) 5.207 ms 5.184 ms core0.fra.hetzner.com (213.239.252.29) 5.049 ms
5 72.14.218.94 (72.14.218.94) 5.273 ms 5.249 ms 72.14.218.176 (72.14.218.176) 4.990 ms
6 108.170.251.193 (108.170.251.193) 5.139 ms * 5.019 ms
7 209.85.241.75 (209.85.241.75) 5.834 ms 216.239.40.58 (216.239.40.58) 5.092 ms 172.253.64.119 (172.253.64.119) 5.707 ms
8 108.170.251.144 (108.170.251.144) 15.292 ms zrh04s05-in-f110.1e100.net (172.217.18.110) 4.952 ms 4.903 ms
答案1
我也遇到過 Hetzner 發來的這些電子郵件，並找到了解決方案。
在 Hetzner 中，您有兩種類型的附加 IP 位址可與專用伺服器一起使用：單一 IPv4 和 IPv4 子網路。對於每個 IP，您都會獲得一個 MAC 位址，並且必須在新 VM 執行個體的網路介面上使用該 MAC。對於每個附加子網，您必須設定一個新網絡，並在該網絡和eth0伺服器的預設網絡（與 關聯）之間設定路由。
在 XenServer 中，這可以使用 Linux 控制台來完成：
xe network-create name-label="Additional network" name-description="46.xx.yy.zz/28"
xapi0這將建立一個連接到XenServer中新橋接器（預設）的新網路。然後將網路的第一個可用 IP 位址（根據其網路遮罩）指派給該網橋：
ip addr add 46.xx.yy.1/28 dev xapi0
現在，您可以新增新的虛擬機，並將自動產生的 MAC 連接到新建立的網路而不是預設網路。流量將在 XenServer 內部進行交換和路由。
完成此設定後，我得到了 Hetzner 網路團隊的確認，只允許 MAC 在交換器連接埠上可見。