diff --git a/vmm/sandbox/src/client.rs b/vmm/sandbox/src/client.rs
index de1a5411..fb76c67f 100644
--- a/vmm/sandbox/src/client.rs
+++ b/vmm/sandbox/src/client.rs
@@ -15,7 +15,11 @@ limitations under the License.
 */
 
 use std::{
-    os::unix::io::{IntoRawFd, RawFd},
+    io::{BufRead, BufReader, Write},
+    os::unix::{
+        io::{IntoRawFd, RawFd},
+        net::UnixStream,
+    },
     time::Duration,
 };
 
@@ -30,17 +34,12 @@ use nix::{
     time::{clock_gettime, ClockId},
     unistd::close,
 };
-use tokio::{
-    io::{AsyncReadExt, AsyncWriteExt},
-    net::UnixStream,
-    time::timeout,
-};
+use tokio::time::timeout;
 use ttrpc::{context::with_timeout, r#async::Client};
 use vmm_common::api::{sandbox::*, sandbox_ttrpc::SandboxServiceClient};
 
 use crate::network::{NetworkInterface, Route};
 
-const HVSOCK_RETRY_TIMEOUT_IN_MS: u64 = 10;
 const TIME_SYNC_PERIOD: u64 = 60;
 const TIME_DIFF_TOLERANCE_IN_MS: u64 = 10;
 
@@ -68,7 +67,11 @@ async fn new_ttrpc_client(address: &str) -> Result<Client> {
 
     let client = timeout(Duration::from_secs(ctx_timeout), fut)
         .await
-        .map_err(|_| anyhow!("{}s timeout connecting socket: {}", ctx_timeout, last_err))?;
+        .map_err(|_| {
+            let e = anyhow!("{}s timeout connecting socket: {}", ctx_timeout, last_err);
+            error!("{}", e);
+            e
+        })?;
     Ok(client)
 }
 
@@ -162,41 +165,28 @@ async fn connect_to_hvsocket(address: &str) -> Result<RawFd> {
         if v.len() < 2 {
             return Err(anyhow!("hvsock address {} should not less than 2", address).into());
         }
-        (v[0], v[1])
+        (v[0].to_string(), v[1].to_string())
     };
 
-    let fut = async {
-        let mut stream = UnixStream::connect(addr).await?;
-
-        match stream.write(format!("CONNECT {}\n", port).as_bytes()).await {
-            Ok(_) => {
-                let mut buf = [0; 4096];
-                match stream.read(&mut buf).await {
-                    Ok(0) => Err(anyhow!("stream closed")),
-                    Ok(n) => {
-                        if String::from_utf8(buf[..n].to_vec())
-                            .unwrap_or_default()
-                            .contains("OK")
-                        {
-                            return Ok(stream.into_std()?.into_raw_fd());
-                        }
-                        Err(anyhow!("failed to connect"))
-                    }
-                    Err(ref e) if e.kind() == std::io::ErrorKind::WouldBlock => {
-                        Err(anyhow!("{}", e))
-                    }
-                    Err(e) => Err(anyhow!("failed to read from hvsock: {}", e)),
-                }
-            }
-            Err(ref e) if e.kind() == std::io::ErrorKind::WouldBlock => Err(anyhow!("{}", e)),
-            Err(e) => Err(anyhow!("failed to write CONNECT to hvsock: {}", e)),
+    tokio::task::spawn_blocking(move || {
+        let mut stream =
+            UnixStream::connect(&addr).map_err(|e| anyhow!("failed to connect hvsock: {}", e))?;
+        stream
+            .write_all(format!("CONNECT {}\n", port).as_bytes())
+            .map_err(|e| anyhow!("hvsock connected but failed to write CONNECT: {}", e))?;
+
+        let mut response = String::new();
+        BufReader::new(&stream)
+            .read_line(&mut response)
+            .map_err(|e| anyhow!("CONNECT sent but failed to get response: {}", e))?;
+        if response.starts_with("OK") {
+            Ok(stream.into_raw_fd())
+        } else {
+            Err(anyhow!("CONNECT sent but response is not OK: {}", response).into())
         }
-        .map_err(Error::Other)
-    };
-
-    timeout(Duration::from_millis(HVSOCK_RETRY_TIMEOUT_IN_MS), fut)
-        .await
-        .map_err(|_| anyhow!("hvsock retry {}ms timeout", HVSOCK_RETRY_TIMEOUT_IN_MS))?
+    })
+    .await
+    .map_err(|e| anyhow!("failed to spawn blocking task: {}", e))?
 }
 
 pub fn unix_sock(r#abstract: bool, socket_path: &str) -> Result<UnixAddr> {
diff --git a/vmm/sandbox/src/cloud_hypervisor/client.rs b/vmm/sandbox/src/cloud_hypervisor/client.rs
index b00ab91a..4771ca94 100644
--- a/vmm/sandbox/src/cloud_hypervisor/client.rs
+++ b/vmm/sandbox/src/cloud_hypervisor/client.rs
@@ -16,7 +16,6 @@ limitations under the License.
 
 use std::{
     os::unix::net::UnixStream,
-    path::Path,
     thread::sleep,
     time::{Duration, SystemTime},
 };
@@ -24,7 +23,7 @@ use std::{
 use anyhow::anyhow;
 use api_client::{simple_api_command, simple_api_full_command_with_fds_and_response};
 use containerd_sandbox::error::Result;
-use log::{error, trace};
+use log::error;
 
 use crate::{
     cloud_hypervisor::devices::{block::DiskConfig, AddDeviceResponse, RemoveDeviceRequest},
@@ -38,25 +37,26 @@ pub struct ChClient {
 }
 
 impl ChClient {
-    pub fn new<P: AsRef<Path>>(socket_path: P) -> Result<Self> {
+    pub async fn new(socket_path: String) -> Result<Self> {
         let start_time = SystemTime::now();
-        loop {
+        tokio::task::spawn_blocking(move || loop {
             match UnixStream::connect(&socket_path) {
                 Ok(socket) => {
                     return Ok(Self { socket });
                 }
                 Err(e) => {
-                    trace!("failed to create client: {:?}", e);
                     if start_time.elapsed().unwrap().as_secs()
                         > CLOUD_HYPERVISOR_START_TIMEOUT_IN_SEC
                     {
-                        error!("failed to create client: {:?}", e);
+                        error!("failed to connect api server: {:?}", e);
                         return Err(anyhow!("timeout connect client, {}", e).into());
                     }
                     sleep(Duration::from_millis(10));
                 }
             }
-        }
+        })
+        .await
+        .map_err(|e| anyhow!("failed to spawn a task {}", e))?
     }
 
     pub fn hot_attach(&mut self, device_info: DeviceInfo) -> Result<String> {
diff --git a/vmm/sandbox/src/cloud_hypervisor/mod.rs b/vmm/sandbox/src/cloud_hypervisor/mod.rs
index 0478b2f5..41dea8b2 100644
--- a/vmm/sandbox/src/cloud_hypervisor/mod.rs
+++ b/vmm/sandbox/src/cloud_hypervisor/mod.rs
@@ -110,7 +110,7 @@ impl CloudHypervisorVM {
     }
 
     async fn create_client(&self) -> Result<ChClient> {
-        ChClient::new(&self.config.api_socket)
+        ChClient::new(self.config.api_socket.to_string()).await
     }
 
     fn get_client(&mut self) -> Result<&mut ChClient> {