无法连接到Cassandra Docker容器
问题描述：
我有官方的Cassandra docker容器正在运行，但我无法从示例控制台应用程序访问。我使用Hyper-V无法连接到Cassandra Docker容器
我使用下面的命令创建容器使用泊坞窗的Windows：docker run --name dev-cassandra -d cassandra:latest
当我运行它给下面的错误应用
An unhandled exception of type 'Cassandra.NoHostAvailableException' occurred in Cassandra.dll
示例代码
class Program
{
static void Main(string[] args)
{
var cluster = Cassandra.Cluster.Builder().AddContactPoint("172.17.0.2").Build();
var session = cluster.Connect("Excelsior");
var rs = session.Execute("SELECT * FROM sample_table");
//Iterate through the RowSet
foreach (var row in rs)
{
var value = row.GetValue<int>("sample_int_column");
//do something with the value
}
Console.WriteLine("Hello World!");
}
}
容器正在运行我通过运行以下命令检查：docker ps
获取网络信息，我跑这个命令：network inspect bridge
[
{
"Name": "bridge",
"Id": "010bdd729d44a99183e45723626576fa6ce607069fb5ca0f52606eaa5395b573",
"Created": "2017-05-05T22:46:13.4234063Z",
"Scope": "local",
"Driver": "bridge",
"EnableIPv6": false,
"IPAM": {
"Driver": "default",
"Options": null,
"Config": [
{
"Subnet": "172.17.0.0/16",
"Gateway": "172.17.0.1"
}
]
},
"Internal": false,
"Attachable": false,
"Containers": {
"6f6a0c0d2f77a03bc0f665d17d7c1d134667bc614e1ed53025b8b1c1c251960b": {
"Name": "dev-cassandra",
"EndpointID": "bded37dd1e6694705e045848b918ef35f9b7983e00f267f311d66a560a5f2f13",
"MacAddress": "02:42:ac:11:00:02",
"IPv4Address": "172.17.0.2/16",
"IPv6Address": ""
}
},
"Options": {
"com.docker.network.bridge.default_bridge": "true",
"com.docker.network.bridge.enable_icc": "true",
"com.docker.network.bridge.enable_ip_masquerade": "true",
"com.docker.network.bridge.host_binding_ipv4": "0.0.0.0",
"com.docker.network.bridge.name": "docker0",
"com.docker.network.driver.mtu": "1500"
},
"Labels": {}
}
]
我也跑这个COMAND docker inspect cassandra获取配置。泊坞窗。
[
{
"Id": "sha256:069269e2357899979df679173096db557fbdd84a82ffd2b08b139f974a36457a",
"RepoTags": [
"cassandra:latest"
],
"RepoDigests": [
"[email protected]:b7fca4d04fdaa10ba4f187d74649f4cd59a4b5018253d58b837cdd1b02ddfe3f"
],
"Parent": "",
"Comment": "",
"Created": "2017-03-21T20:13:44.022375976Z",
"Container": "ec6b65101d9f5d335e2820809d2dda12eabaebfb21b2f362d67066521468b809",
"ContainerConfig": {
"Hostname": "7e9ec6cde4d1",
"Domainname": "",
"User": "",
"AttachStdin": false,
"AttachStdout": false,
"AttachStderr": false,
"ExposedPorts": {
"7000/tcp": {},
"7001/tcp": {},
"7199/tcp": {},
"9042/tcp": {},
"9160/tcp": {}
},
"Tty": false,
"OpenStdin": false,
"StdinOnce": false,
"Env": [
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
"GOSU_VERSION=1.7",
"GPG_KEYS=514A2AD631A57A16DD0047EC749D6EEC0353B12C \tA26E528B271F19B9E5D8E19EA278B781FE4B2BDA",
"CASSANDRA_VERSION=3.10",
"CASSANDRA_CONFIG=/etc/cassandra"
],
"Cmd": [
"/bin/sh",
"-c",
"#(nop) ",
"CMD [\"cassandra\" \"-f\"]"
],
"ArgsEscaped": true,
"Image": "sha256:ada42f145ac8582ed811da1a1353369d4ac65d5830f9a80f657433676f1802de",
"Volumes": {
"/var/lib/cassandra": {}
},
"WorkingDir": "",
"Entrypoint": [
"/docker-entrypoint.sh"
],
"OnBuild": [],
"Labels": {}
},
"DockerVersion": "1.12.6",
"Author": "",
"Config": {
"Hostname": "7e9ec6cde4d1",
"Domainname": "",
"User": "",
"AttachStdin": false,
"AttachStdout": false,
"AttachStderr": false,
"ExposedPorts": {
"7000/tcp": {},
"7001/tcp": {},
"7199/tcp": {},
"9042/tcp": {},
"9160/tcp": {}
},
"Tty": false,
"OpenStdin": false,
"StdinOnce": false,
"Env": [
"PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin",
"GOSU_VERSION=1.7",
"GPG_KEYS=514A2AD631A57A16DD0047EC749D6EEC0353B12C \tA26E528B271F19B9E5D8E19EA278B781FE4B2BDA",
"CASSANDRA_VERSION=3.10",
"CASSANDRA_CONFIG=/etc/cassandra"
],
"Cmd": [
"cassandra",
"-f"
],
"ArgsEscaped": true,
"Image": "sha256:ada42f145ac8582ed811da1a1353369d4ac65d5830f9a80f657433676f1802de",
"Volumes": {
"/var/lib/cassandra": {}
},
"WorkingDir": "",
"Entrypoint": [
"/docker-entrypoint.sh"
],
"OnBuild": [],
"Labels": {}
},
"Architecture": "amd64",
"Os": "linux",
"Size": 385729595,
"VirtualSize": 385729595,
"GraphDriver": {
"Name": "overlay2",
"Data": {
"LowerDir": "/var/lib/docker/overlay2/5cdd50711a30b35eac48952b286bb61e9c3d443ee07d5715c20c536a81d810e0/diff:/var/lib/docker/overlay2/b602b88eae488165e8c401065eea689acd103950f7ebdf65347ac28e87ef936f/diff:/var/lib/docker/overlay2/81c6762aa1ddd5b7c44ca8c1cff05f718cedf2cc0ba40f6f42775a166e218205/diff:/var/lib/docker/overlay2/529349dc7ce84eb4fc54ed4f677d96c5f0fdce90a26c1ed15251304dfc0e35ac/diff:/var/lib/docker/overlay2/f121b1f27ad21ceb0e2d7dbadf8c8ef86483fb52d37652fb3a1527e8d555408d/diff:/var/lib/docker/overlay2/07df2fac46233c52197c3f2c0604cbc99b7e1cc2958f22688f6e2fbd8b94840f/diff:/var/lib/docker/overlay2/373f1208a1f44a068bcf92f9d976b67f541700bee1cbd339b7c63507752581c0/diff:/var/lib/docker/overlay2/9a89ae5b436a90085a5026ed21aa094faa070b856ef375b5b8f8718543c3b281/diff:/var/lib/docker/overlay2/9ca3fdc3437863f6626a39f0b60cc73bb1bda813317b630e011d481a81703e43/diff:/var/lib/docker/overlay2/66b2788945d88001b6fa13001952691c7039e634237d434d80b224352284ac2a/diff:/var/lib/docker/overlay2/1834e9892519424500e3e5088cadb542f24054979974cf89fbe28ad4053ca73d/diff",
"MergedDir": "/var/lib/docker/overlay2/900c01f3f2a541d26cde9813f21c36ae4cf44568ac7a33d24246ef14b3c610d8/merged",
"UpperDir": "/var/lib/docker/overlay2/900c01f3f2a541d26cde9813f21c36ae4cf44568ac7a33d24246ef14b3c610d8/diff",
"WorkDir": "/var/lib/docker/overlay2/900c01f3f2a541d26cde9813f21c36ae4cf44568ac7a33d24246ef14b3c610d8/work"
}
},
"RootFS": {
"Type": "layers",
"Layers": [
"sha256:5d6cbe0dbcf9a675e86aa0fbedf7ed8756d557c7468d6a7c64bde7fa9e029636",
"sha256:aa4c186185aa90ac9c821a3c328cfbb21672dad969c9f9bc5151a5f4c341f970",
"sha256:9d82a392a50d6b0a8cb4e717d02b83727429118f7f215c7a5ed5f7006557b525",
"sha256:23f60ed07f46279b0e9b13521bb74570bf2d0c6b2763d5b072de4f6fd59cff3f",
"sha256:8a2c71106b17a02037ab131a45d9b076338121abc9d12aa9a1bc2f818514cda0",
"sha256:da91891b3c4c6cdfaff6960288166789da406078a20eddb5e961f5383d62a69f",
"sha256:43ab122f258f04014a344119e7cf8187c055a618993398973f0c7eeafa5def83",
"sha256:bcdcd03011e6ae49a63e85a099fd0067d7676e04e85eebecf65baa43823214ab",
"sha256:08adfaf9cb5b340c7a3abbe98be3c30cc0a789a049206bf4735c6e297e12eb55",
"sha256:6a2d68da5af1253a40cf952283f66b5e3ed0c8a55e34c6aac544358ed310a452",
"sha256:93cb898347afdcaf66fbe8ebf1d1aa1e8ce77f4e9d73fb20e5f5531672b24bbd",
"sha256:5b4b685f0f11fa1d4479fdd127852b16322b85ec1568d36cf18f40f99d37bd67"
]
}
}
]
答
假设你的C＃代码运行在Visual Studio在本地计算机上（而不是在一个码头工人容器还），你有这里有两个问题。首先，您没有将Cassandra容器上的任何端口暴露给主机。您需要的端口号是9042，因为这是CQL二进制协议接受客户端连接的地方。因此，例如暴露集装箱码头9042为主机端口9042，你需要做的：
> docker run --name dev-cassandra -d -p 9042:9042 cassandra:latest
由于您使用的码头工人的Windows，你在主机上暴露这种方式现在将任何端口可通过localhost或127.0.0.1获得。因此，第二个问题就是您在从主机上运行的代码连接到Docker容器时尝试使用的IP地址。您使用的IP地址是Docker内部桥接网络上的容器，因此只有当您的C＃代码也在Docker容器（连接到同一个网桥网络）中运行时，IP地址才会起作用。
你的代码来创建集群应该是：
var cluster = Cassandra.Cluster.Builder().AddContactPoint("127.0.0.1").Build();
驱动程序会自动默认端口9042。希望有所帮助！
+0
非常好的解释，谢谢！ – Vlad
我对Windows VM配置并不熟悉，所以请原谅我在这里的无知，但是......应该不要链接或暴露您的容器中的端口？它看起来像这个主机是不可见的程序。您是否尝试使用C＃程序中的IP来查找虚拟主机（guest），而不使用Cassandra的连接器？ – Edmon