diff --git a/build.gradle.kts b/build.gradle.kts
index 69f72163..96bdffa5 100644
--- a/build.gradle.kts
+++ b/build.gradle.kts
@@ -1,4 +1,3 @@
-val ktor_version: String by project
 val kotlin_version: String by project
 
 plugins {
@@ -22,9 +21,15 @@ repositories {
 }
 
 dependencies {
+    val ktor_version = "1.6.8"
+    // ktor server
     implementation("io.ktor:ktor-server-core:$ktor_version")
     implementation("io.ktor:ktor-server-netty:$ktor_version")
 
+    // ktor client
+    implementation("io.ktor:ktor-client-core:$ktor_version")
+    implementation("io.ktor:ktor-client-cio:$ktor_version")
+
     // coroutine
     val coroutine_version = "1.6.0"
     implementation("org.jetbrains.kotlinx:kotlinx-coroutines-core:$coroutine_version")
@@ -39,11 +44,7 @@ dependencies {
     implementation("io.ktor:ktor-auth:$ktor_version")
 
     // serialization
-    val jackson_version = "2.13.0"
-    implementation("org.jetbrains.kotlinx:kotlinx-serialization-json:1.3.0")
     implementation("io.ktor:ktor-jackson:$ktor_version")
-    implementation("com.fasterxml.jackson.datatype:jackson-datatype-jdk8:$jackson_version")
-    implementation("com.fasterxml.jackson.datatype:jackson-datatype-jsr310:$jackson_version")
 
     // Redis
     implementation("io.lettuce:lettuce-core:6.1.5.RELEASE")
diff --git a/gradle.properties b/gradle.properties
index df1eb037..41c829c5 100644
--- a/gradle.properties
+++ b/gradle.properties
@@ -1,3 +1,2 @@
-ktor_version=1.6.5
 kotlin_version=1.5.31
 kotlin.code.style=official
diff --git a/src/main/kotlin/cn/edu/buaa/scs/controller/plugins/ContentNegotiation.kt b/src/main/kotlin/cn/edu/buaa/scs/controller/plugins/ContentNegotiation.kt
index 5f512b3b..d919e18d 100644
--- a/src/main/kotlin/cn/edu/buaa/scs/controller/plugins/ContentNegotiation.kt
+++ b/src/main/kotlin/cn/edu/buaa/scs/controller/plugins/ContentNegotiation.kt
@@ -1,25 +1,14 @@
 package cn.edu.buaa.scs.controller.plugins
 
-import cn.edu.buaa.scs.utils.InstantSerializer
-import com.fasterxml.jackson.datatype.jdk8.Jdk8Module
-import com.fasterxml.jackson.datatype.jsr310.JavaTimeModule
 import io.ktor.application.*
 import io.ktor.features.*
 import io.ktor.jackson.*
 import org.ktorm.jackson.KtormModule
-import java.time.Instant
 
 fun Application.configureContentNegotiation() {
     install(ContentNegotiation) {
         jackson {
             registerModule(KtormModule())
-            registerModule(JavaTimeModule().apply {
-                addSerializer(
-                    Instant::class.java,
-                    InstantSerializer()
-                )
-            })
-            registerModule(Jdk8Module())
         }
     }
 }
\ No newline at end of file
diff --git a/src/main/kotlin/cn/edu/buaa/scs/utils/Time.kt b/src/main/kotlin/cn/edu/buaa/scs/utils/Time.kt
index bb42cda6..35d826e1 100644
--- a/src/main/kotlin/cn/edu/buaa/scs/utils/Time.kt
+++ b/src/main/kotlin/cn/edu/buaa/scs/utils/Time.kt
@@ -1,12 +1,8 @@
 package cn.edu.buaa.scs.utils
 
-import com.fasterxml.jackson.core.JsonGenerator
-import com.fasterxml.jackson.databind.SerializerProvider
-import com.fasterxml.jackson.databind.ser.std.StdSerializer
 import java.time.Instant
 import java.time.LocalDateTime
 import java.time.ZoneId
-import java.time.ZoneOffset
 import java.time.format.DateTimeFormatter
 
 const val defaultDateTimeFormatter = "yyyy/MM/dd HH:mm:ss"
@@ -27,12 +23,4 @@ fun Long.formatDateTime(formatString: String = defaultDateTimeFormatter): String
 object TimeUtil {
     fun currentDateTime(): String =
         System.currentTimeMillis().formatDateTime()
-}
-
-class InstantSerializer : StdSerializer<Instant>(Instant::class.java) {
-    override fun serialize(value: Instant?, gen: JsonGenerator?, provider: SerializerProvider?) {
-        val formatter = DateTimeFormatter.ofPattern("yyyy/MM/dd HH:mm:ss")
-            .withZone(ZoneOffset.ofHours(8))
-        gen?.writeString(value?.let { formatter.format(it) })
-    }
 }
\ No newline at end of file
diff --git a/src/main/kotlin/cn/edu/buaa/scs/vm/IVmClient.kt b/src/main/kotlin/cn/edu/buaa/scs/vm/IVmClient.kt
new file mode 100644
index 00000000..8b8ba4ca
--- /dev/null
+++ b/src/main/kotlin/cn/edu/buaa/scs/vm/IVmClient.kt
@@ -0,0 +1,4 @@
+package cn.edu.buaa.scs.vm
+
+interface IVmClient {
+}
\ No newline at end of file
diff --git a/src/main/kotlin/cn/edu/buaa/scs/vm/OldVmClient.kt b/src/main/kotlin/cn/edu/buaa/scs/vm/OldVmClient.kt
new file mode 100644
index 00000000..92cb5242
--- /dev/null
+++ b/src/main/kotlin/cn/edu/buaa/scs/vm/OldVmClient.kt
@@ -0,0 +1,77 @@
+package cn.edu.buaa.scs.vm
+
+import cn.edu.buaa.scs.utils.getConfigString
+import io.ktor.application.*
+import io.ktor.client.*
+import io.ktor.client.engine.cio.*
+import io.ktor.client.features.*
+import io.ktor.client.request.*
+import io.ktor.http.*
+import io.ktor.http.content.*
+import kotlinx.coroutines.Dispatchers
+import kotlinx.coroutines.withContext
+import java.io.ByteArrayInputStream
+import java.net.URLDecoder
+import javax.xml.parsers.DocumentBuilder
+import javax.xml.parsers.DocumentBuilderFactory
+
+object OldVmClient : IVmClient {
+    internal lateinit var svcPath: String
+
+    private val client: HttpClient by lazy {
+        HttpClient(CIO) {
+            engine {
+                maxConnectionsCount = 1000
+                endpoint {
+                    maxConnectionsPerRoute = 100
+                    pipelineMaxSize = 20
+                    keepAliveTime = 5000
+                    connectTimeout = 5000
+                    connectAttempts = 5
+                }
+
+            }
+            defaultRequest {
+                header("SOAPAction", "\"\"")
+            }
+        }
+    }
+
+    private suspend fun <T> baseAction(req: String, respTag: String, convert: (String) -> T): T {
+        val resp = client.post<String>(svcPath) {
+            body = TextContent(req, contentType = ContentType.Text.Xml)
+        }
+        val builder: DocumentBuilder = DocumentBuilderFactory.newInstance().newDocumentBuilder()
+        val doc = withContext(Dispatchers.IO) {
+            ByteArrayInputStream(resp.toByteArray(Charsets.UTF_8)).use {
+                builder.parse(it)
+            }
+        }
+        val node = doc.getElementsByTagName(respTag).item(0)
+        return convert(URLDecoder.decode(node.textContent, Charsets.UTF_8))
+    }
+
+    suspend fun getVmInfo(name: String): String {
+        return baseAction(
+            """
+                <soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:vcm="http://vm.manager.buaa.edu.cn/VCManager">
+                   <soapenv:Header/>
+                   <soapenv:Body>
+                      <vcm:GetVMInfo>
+                         <name>$name</name>
+                      </vcm:GetVMInfo>
+                   </soapenv:Body>
+                </soapenv:Envelope>
+            """.trimIndent(),
+            "GetVMInfoReturn"
+        ) {
+            it
+        }
+    }
+}
+
+@Suppress("unused")
+fun Application.oldVmClientModule() {
+    val endpoint = getConfigString("oldVmManager.endpoint")
+    OldVmClient.svcPath = endpoint
+}
\ No newline at end of file
diff --git a/src/test/kotlin/cn/edu/buaa/scs/vm/OldVmClientTest.kt b/src/test/kotlin/cn/edu/buaa/scs/vm/OldVmClientTest.kt
new file mode 100644
index 00000000..b1034185
--- /dev/null
+++ b/src/test/kotlin/cn/edu/buaa/scs/vm/OldVmClientTest.kt
@@ -0,0 +1,17 @@
+package cn.edu.buaa.scs.vm
+
+import cn.edu.buaa.scs.testEnv
+import io.ktor.server.testing.*
+import kotlinx.coroutines.runBlocking
+import org.junit.jupiter.api.Test
+
+class OldVmClientTest {
+    @Test
+    fun testGetVmInfo() {
+        withApplication(testEnv) {
+            runBlocking {
+                println(OldVmClient.getVmInfo("debian11-ks-2"))
+            }
+        }
+    }
+}
\ No newline at end of file