Format Rust code using rustfmt

.github/workflows/release.yml

@@ -1,117 +1,140 @@
 name: Rust static build and publish
+
 on:
   push:
     tags:
-    - '*'
+      - 'v*.*.*'
+
 env:
   CARGO_TERM_COLOR: always
-  BUILD_TARGET: x86_64-unknown-linux-musl
   BINARY_NAME: rexec
+
 jobs:
   build:
     name: Build static binary
-    runs-on: ubuntu-latest
+    runs-on: ${{ matrix.os }}
+    strategy:
+      matrix:
+        os: [ubuntu-latest, windows-latest, macos-latest]
+        include:
+          - os: ubuntu-latest
+            build_target: x86_64-unknown-linux-musl
+            platform_name: linux-amd64
+          - os: windows-latest
+            build_target: x86_64-pc-windows-msvc
+            platform_name: windows-amd64
+          - os: macos-latest
+            build_target: aarch64-apple-darwin
+            platform_name: macos-arm64
     permissions:
       contents: write
     steps:
-      - uses: actions/checkout@v3
+      - uses: actions/checkout@v4
+      
+      - name: Cache Cargo registry
+        uses: actions/cache@v4
+        with:
+          path: ~/.cargo/registry
+          key: ${{ runner.os }}-cargo-registry-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-cargo-registry-
+      
+      - name: Cache Cargo index
+        uses: actions/cache@v4
+        with:
+          path: ~/.cargo/git
+          key: ${{ runner.os }}-cargo-index-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-cargo-index-
+      
+      - name: Cache Cargo build
+        uses: actions/cache@v4
+        with:
+          path: target
+          key: ${{ runner.os }}-cargo-build-${{ hashFiles('**/Cargo.lock') }}
+          restore-keys: |
+            ${{ runner.os }}-cargo-build-
+
       - uses: dtolnay/rust-toolchain@stable
+      
       - uses: mbrobbel/rustfmt-check@master
         with:
           token: ${{ secrets.GITHUB_TOKEN }}
-      - name: Build-musl
+          
+      - name: Install rust targets
+        run: rustup target add ${{ matrix.build_target }}
+        
+      - name: Build Linux MUSL
+        if: matrix.os == 'ubuntu-latest'
         uses: gmiam/rust-musl-action@master
         with:
-          args: cargo build --target $BUILD_TARGET --release
+          args: cargo build --target ${{ matrix.build_target }} --release
+          
+      - name: Build MacOS
+        if: matrix.os == 'macos-latest'
+        run: cargo build --target ${{ matrix.build_target }} --release
+          
+      - name: Build Windows
+        if: matrix.os == 'windows-latest'
+        run: cargo build --target ${{ matrix.build_target }} --release
+          
+      - name: Upload artifact
+        uses: actions/upload-artifact@v4
+        with:
+          name: ${{ env.BINARY_NAME }}_${{ matrix.platform_name }}
+          path: target/${{ matrix.build_target }}/release/${{ env.BINARY_NAME }}*
+
+  release:
+    name: Create Release Page
+    needs: build
+    runs-on: ubuntu-latest
+    outputs:
+      upload_url: ${{ steps.create_release.outputs.upload_url }}
+    permissions:
+      contents: write
+    steps:
+      - uses: actions/checkout@v4
       - name: Get version
         run: echo "VERSION=$(grep -P '^version = \"\d+\.\d+\.\d+\"' Cargo.toml | awk -F '\"' '{print $2}')" >> $GITHUB_ENV
       - name: Show version
         run: echo ${{ env.VERSION }}
-      - uses: actions/upload-artifact@v3.1.2
-        name: Upload artifact
-        with:
-          name: ${{ env.BINARY_NAME }}_${{ env.VERSION }}_${{ env.BUILD_TARGET }}
-          path: target/${{ env.BUILD_TARGET }}/release/${{ env.BINARY_NAME }}
-  build_arch:
-    name: Arch Linux package
-    runs-on: ubuntu-latest
-    needs: ["build"]
-    container:
-      image: archlinux:base-devel
-      options: --user 1001
-    permissions:
-      contents: write
-    steps:
-      - uses: actions/checkout@v3
-      - name: Get version
-        run: echo "VERSION=$(grep -P '^version = \"\d+\.\d+\.\d+\"' Cargo.toml | awk -F '\"' '{print $2}')" >> $GITHUB_ENV
-      - uses: actions/download-artifact@master
-        name: Download
-        id: download_binary
-        with:
-          name: ${{ env.BINARY_NAME }}_${{ env.VERSION }}_${{ env.BUILD_TARGET }}
-          path: ${{ env.BINARY_NAME }}_${{ env.VERSION }}_${{ env.BUILD_TARGET }}
-      - name: Prepare build env
-        run: |
-          mkdir -p target/${{ env.BUILD_TARGET }}/release/
-          mv ${{ env.BINARY_NAME }}_${{ env.VERSION }}_${{ env.BUILD_TARGET }}/rexec target/${{ env.BUILD_TARGET }}/release/
-          sed -i -e "s/some_ver/${{ env.VERSION }}/" PKGBUILD
-      - name: Build ZST package
-        run: |
-          makepkg -f
-      - uses: actions/upload-artifact@v3.1.2
-        name: Upload artifact
-        with:
-          name: ${{ env.BINARY_NAME }}_${{ env.VERSION }}_${{ env.BUILD_TARGET }}.zst
-          path: ${{ github.workspace }}/*zst
-
-
-  release:
-    name: Making New Release ^_^
-    needs:
-      - build
-      - build_arch
-    runs-on: ubuntu-latest
-    permissions:
-      contents: write
-    steps:
-    - uses: actions/checkout@v3
-    - name: Get version
-      run: echo "VERSION=$(grep -P '^version = \"\d+\.\d+\.\d+\"' Cargo.toml | awk -F '\"' '{print $2}')" >> $GITHUB_ENV
-    - uses: actions/download-artifact@master
-      name: Download binary
-      id: download_binary
-      with:
-        name: ${{ env.BINARY_NAME }}_${{ env.VERSION }}_${{ env.BUILD_TARGET }}
-        path: ${{ env.BINARY_NAME }}_${{ env.VERSION }}_${{ env.BUILD_TARGET }}
-    - uses: actions/download-artifact@master
-      id: download_pkg
-      name: Download ZST package
-      with:
-        name: ${{ env.BINARY_NAME }}_${{ env.VERSION }}_${{ env.BUILD_TARGET }}.zst
-        path: ${{ env.BINARY_NAME }}_${{ env.VERSION }}_${{ env.BUILD_TARGET }}.zst
       - uses: ncipollo/release-action@v1
-      name: Update release page
+        id: create_release
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
         with:
-        artifacts: "${{ steps.download_binary.outputs.download-path }}/*,${{ steps.download_pkg.outputs.download-path }}/*"
           allowUpdates: true
-        body: Static musl build for x86_64-linux and Arch Linux package
+          body: "Release rexec ${{ env.VERSION }}. Static build for Linux (x86_64), Windows (x86_64) и MacOS (arm64)."
 
-  dispatch:
+  upload:
-    name: Notify my Arch Repo
+    name: Upload Release Assets
-    needs:
+    needs: release
-      - build
+    runs-on: ${{ matrix.os }}
-      - build_arch
+    strategy:
-      - release
+      matrix:
-    runs-on: ubuntu-latest
+        os: [ubuntu-latest, windows-latest, macos-latest]
-    timeout-minutes: 5
+        include:
+          - os: ubuntu-latest
+            platform_name: linux-amd64
+          - os: windows-latest
+            platform_name: windows-amd64
+          - os: macos-latest
+            platform_name: macos-arm64
     steps:
-      - name: Dispatch to workflows
+      - uses: actions/checkout@v4
-        run: |
+      
-          curl -L \
+      - uses: actions/download-artifact@v4
-            -X POST \
+        name: Download ${{ matrix.platform_name }} artifact
-            -H "Accept: application/vnd.github+json" \
+        with:
-            -H "Authorization: Bearer ${{ secrets.ACTIONS_KEY }}" \
+          name: ${{ env.BINARY_NAME }}_${{ matrix.platform_name }}
-            -H "X-GitHub-Api-Version: 2022-11-28" \
+          path: ${{ env.BINARY_NAME }}_${{ matrix.platform_name }}
-            https://api.github.com/repos/house-of-vanity/arch_repo/dispatches \
+          
-            -d '{"event_type":"new_package","client_payload":{}}'
+      - name: Upload Release Asset
+        uses: actions/upload-release-asset@v1
+        env:
+          GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
+        with:
+          upload_url: ${{ needs.release.outputs.upload_url }}
+          asset_path: ${{ env.BINARY_NAME }}_${{ matrix.platform_name }}/${{ env.BINARY_NAME }}${{ matrix.platform_name == 'windows-amd64' && '.exe' || '' }}
+          asset_name: ${{ env.BINARY_NAME }}_${{ matrix.platform_name }}${{ matrix.platform_name == 'windows-amd64' && '.exe' || '' }}
+          asset_content_type: application/octet-stream

.github/workflows/update_repo.yml

@@ -1,15 +0,0 @@
-name: Dispatcher
-on: ["push"]
-
-jobs:
-  dispatch:
-    name: Dispatch
-    runs-on: ubuntu-latest
-    timeout-minutes: 5
-    steps:
-      - name: Dispatch to workflows
-        run: |
-            curl -H "Accept: application/vnd.github.everest-preview+json" \
-            -H "Authorization: token ${{ secrets.ACTIONS_KEY }}" \
-            --request POST \
-            --data '{"event_type": "some_event", "client_payload": { "foo": "bar" }}' https://api.github.com/repos/house-of-vanity/arch_repo/dispatches

CHANGELOG.md

@@ -6,6 +6,14 @@ The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
 
+
+## [1.1.0] - 2023-09-13
+
+### Improved
+
+- Logging. Fix bugs 
+
+
 ## [1.0.7] - 2023-08-31
 
 ### Changed

Cargo.lock

@@ -1,6 +1,6 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
-version = 3
+version = 4
 
 [[package]]
 name = "aho-corasick"
@@ -244,6 +244,31 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "crossbeam-deque"
+version = "0.8.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "9dd111b7b7f7d55b72c0a6ae361660ee5853c9af73f70c3c2ef6858b950e2e51"
+dependencies = [
+ "crossbeam-epoch",
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-epoch"
+version = "0.9.18"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "5b82ac4a3c2ca9c3460964f020e1402edd5753411d7737aa39c3714ad1b5420e"
+dependencies = [
+ "crossbeam-utils",
+]
+
+[[package]]
+name = "crossbeam-utils"
+version = "0.8.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d0a5c400df2834b80a4c3327b3aad3a4c4cd4de0629063962b03235697506a28"
+
 [[package]]
 name = "crypto-common"
 version = "0.1.6"
@@ -1029,6 +1054,26 @@ dependencies = [
  "getrandom",
 ]
 
+[[package]]
+name = "rayon"
+version = "1.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b418a60154510ca1a002a752ca9714984e21e4241e804d32555251faf8b78ffa"
+dependencies = [
+ "either",
+ "rayon-core",
+]
+
+[[package]]
+name = "rayon-core"
+version = "1.12.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1465873a3dfdaa8ae7cb14b4383657caab0b3e8a0aa9ae8e04b044854c8dfce2"
+dependencies = [
+ "crossbeam-deque",
+ "crossbeam-utils",
+]
+
 [[package]]
 name = "redox_syscall"
 version = "0.2.16"
@@ -1066,7 +1111,7 @@ checksum = "436b050e76ed2903236f032a59761c1eb99e1b0aead2c257922771dab1fc8c78"
 
 [[package]]
 name = "rexec"
-version = "1.0.9"
+version = "1.3.1"
 dependencies = [
  "brace-expand",
  "clap 4.3.4",
@@ -1079,6 +1124,7 @@ dependencies = [
  "massh",
  "openssl",
  "question",
+ "rayon",
  "regex",
  "whoami",
 ]

Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "rexec"
-version = "1.1.0"
+version = "1.3.1"
 readme = "https://github.com/house-of-vanity/rexec#readme"
 edition = "2021"
 description = "Parallel SSH executor"
@@ -14,6 +14,7 @@ authors = ["AB <gh@hexor.ru>"]
 
 [dependencies]
 dns-lookup = "2.0.2"
+rayon = "1.10"
 log = "0.4.0"
 env_logger = "0.10.0"
 massh = "0.6.3"

src/main.rs

@@ -1,29 +1,34 @@
-#[macro_use]
 extern crate log;
 
 use std::collections::HashMap;
 use std::fs::read_to_string;
 use std::hash::Hash;
+use std::io::{BufRead, BufReader};
 use std::net::IpAddr;
-use std::process;
+use std::process::{self, Command, Stdio};
+use std::sync::{Arc, Mutex};
+use std::thread;
 
 use clap::Parser;
 use colored::*;
 use dns_lookup::lookup_host;
 use env_logger::Env;
 use itertools::Itertools;
-use log::{error, info};
+use log::{error, info, warn};
 use massh::{MasshClient, MasshConfig, MasshHostConfig, SshAuth};
 use question::{Answer, Question};
+use rayon::prelude::*;
 use regex::Regex;
 
-// Define args
+// Define command-line arguments using the clap library
 #[derive(Parser, Debug)]
 #[command(author = "AB ab@hexor.ru", version, about = "Parallel SSH executor in Rust", long_about = None)]
 struct Args {
-    #[arg(short, long, default_value_t = whoami::username())]
+    /// Username for SSH connections (defaults to current system user)
+    #[arg(short = 'u', short = 'l', long, default_value_t = whoami::username())]
     username: String,
 
+    /// Flag to use known_hosts file for server discovery instead of pattern expansion
     #[arg(
         short,
         long,
@@ -31,6 +36,8 @@ struct Args {
     )]
     known_hosts: bool,
 
+    /// Server name patterns with expansion syntax
+    /// Examples: 'web-[1:12]-io-{prod,dev}' expands to multiple servers
     #[arg(
         short,
         long,
@@ -39,12 +46,15 @@ struct Args {
     )]
     expression: Vec<String>,
 
+    /// Command to execute on each server
     #[arg(short, long, help = "Command to execute on servers")]
     command: String,
 
+    /// Display only exit codes without command output
     #[arg(long, default_value_t = false, help = "Show exit code ONLY")]
     code: bool,
 
+    /// Skip confirmation prompt before executing commands
     #[arg(
         short = 'f',
         long,
@@ -53,21 +63,112 @@ struct Args {
     )]
     noconfirm: bool,
 
+    /// Maximum number of parallel SSH connections
     #[arg(short, long, default_value_t = 100)]
     parallel: i32,
+
+    /// Use the embedded SSH client library instead of system SSH command
+    #[arg(
+        long,
+        help = "Use embedded SSH client instead of system SSH. Does not support 'live output'.",
+        default_value_t = false
+    )]
+    embedded_ssh: bool,
 }
 
-// Represent line from known_hosts file
+/// Host representation for both known_hosts entries and expanded patterns
 #[derive(Debug, Default, Clone, PartialEq, Eq, Hash)]
 struct Host {
+    /// Hostname or IP address as a string
     name: String,
+    /// Resolved IP address (if available)
     ip: Option<IpAddr>,
 }
 
-// Read known_hosts file
+/// Find common domain suffix across all hostnames to simplify output display
+///
+/// This function analyzes all hostnames to identify a common domain suffix
+/// which can be shortened during display to improve readability.
+///
+/// # Arguments
+/// * `hostnames` - A slice of strings containing all server hostnames
+///
+/// # Returns
+/// * `Option<String>` - The common suffix if found, or None
+fn find_common_suffix(hostnames: &[String]) -> Option<String> {
+    if hostnames.is_empty() {
+        return None;
+    }
+
+    // Don't truncate if only one host
+    if hostnames.len() == 1 {
+        return None;
+    }
+
+    let first = &hostnames[0];
+
+    // Start with assumption that the entire first hostname is the common suffix
+    let mut common = first.clone();
+
+    // Iterate through remaining hostnames, reducing the common part
+    for hostname in hostnames.iter().skip(1) {
+        // Exit early if no common part remains
+        if common.is_empty() {
+            return None;
+        }
+
+        // Find common suffix with current hostname
+        let mut new_common = String::new();
+
+        // Search for common suffix by comparing characters from right to left
+        let mut common_chars = common.chars().rev();
+        let mut hostname_chars = hostname.chars().rev();
+
+        loop {
+            match (common_chars.next(), hostname_chars.next()) {
+                (Some(c1), Some(c2)) if c1 == c2 => new_common.insert(0, c1),
+                _ => break,
+            }
+        }
+
+        common = new_common;
+    }
+
+    // Ensure the common part is a valid domain suffix (starts with a dot)
+    if common.is_empty() || !common.starts_with('.') {
+        return None;
+    }
+
+    // Return the identified common suffix
+    Some(common)
+}
+
+/// Shorten hostname by removing the common suffix and replacing with an asterisk
+///
+/// # Arguments
+/// * `hostname` - The original hostname
+/// * `common_suffix` - Optional common suffix to remove
+///
+/// # Returns
+/// * `String` - Shortened hostname or original if no common suffix
+fn shorten_hostname(hostname: &str, common_suffix: &Option<String>) -> String {
+    match common_suffix {
+        Some(suffix) if hostname.ends_with(suffix) => {
+            let short_name = hostname[..hostname.len() - suffix.len()].to_string();
+            format!("{}{}", short_name, "*")
+        }
+        _ => hostname.to_string(),
+    }
+}
+
+/// Read and parse the SSH known_hosts file to extract server names
+///
+/// # Returns
+/// * `Vec<Host>` - List of hosts found in the known_hosts file
 fn read_known_hosts() -> Vec<Host> {
     let mut result: Vec<Host> = Vec::new();
 
+    // Read known_hosts file from the user's home directory
     for line in read_to_string(format!("/home/{}/.ssh/known_hosts", whoami::username()))
         .unwrap()
         .lines()
@@ -82,18 +183,45 @@ fn read_known_hosts() -> Vec<Host> {
     result
 }
 
+/// Expand a numeric range in the format [start:end] to a list of strings
+///
+/// # Arguments
+/// * `start` - Starting number (inclusive)
+/// * `end` - Ending number (inclusive)
+///
+/// # Returns
+/// * `Vec<String>` - List of numbers as strings
 fn expand_range(start: i32, end: i32) -> Vec<String> {
     (start..=end).map(|i| i.to_string()).collect()
 }
 
+/// Expand a comma-separated list in the format {item1,item2,item3} to a list of strings
+///
+/// # Arguments
+/// * `list` - Comma-separated string to expand
+///
+/// # Returns
+/// * `Vec<String>` - List of expanded items
 fn expand_list(list: &str) -> Vec<String> {
     list.split(',').map(|s| s.to_string()).collect()
 }
 
+/// Expand a server pattern string with range and list notation into individual hostnames
+///
+/// Supports two expansion types:
+/// - Range expansion: server-[1:5] → server-1, server-2, server-3, server-4, server-5
+/// - List expansion: server-{prod,dev} → server-prod, server-dev
+///
+/// # Arguments
+/// * `s` - Pattern string to expand
+///
+/// # Returns
+/// * `Vec<Host>` - List of expanded Host objects
 fn expand_string(s: &str) -> Vec<Host> {
     let mut hosts: Vec<Host> = Vec::new();
     let mut result = vec![s.to_string()];
 
+    // First expand all range expressions [start:end]
     while let Some(r) = result.iter().find(|s| s.contains('[')) {
         let r = r.clone();
         let start = r.find('[').unwrap();
@@ -120,6 +248,7 @@ fn expand_string(s: &str) -> Vec<Host> {
         }
     }
 
+    // Then expand all list expressions {item1,item2}
     while let Some(r) = result.iter().find(|s| s.contains('{')) {
         let r = r.clone();
         let start = r.find('{').unwrap();
@@ -138,6 +267,7 @@ fn expand_string(s: &str) -> Vec<Host> {
         }
     }
 
+    // Convert all expanded strings to Host objects
     for hostname in result {
         hosts.push(Host {
             name: hostname.to_string(),
@@ -147,14 +277,294 @@ fn expand_string(s: &str) -> Vec<Host> {
     hosts
 }
 
+/// Execute a command on a single host using the system SSH client
+///
+/// This function runs an SSH command using the system's SSH client,
+/// capturing and displaying output in real-time with proper formatting.
+///
+/// # Arguments
+/// * `hostname` - Target server hostname
+/// * `username` - SSH username
+/// * `command` - Command to execute
+/// * `common_suffix` - Optional common suffix for hostname display formatting
+///
+/// # Returns
+/// * `Result<i32, String>` - Exit code on success or error message
+fn execute_ssh_command(
+    hostname: &str,
+    username: &str,
+    command: &str,
+    common_suffix: &Option<String>,
+) -> Result<i32, String> {
+    let display_name = shorten_hostname(hostname, common_suffix);
+
+    // Display execution start message with shortened hostname
+    println!("\n{} - STARTED", display_name.yellow().bold());
+
+    // Build the SSH command with appropriate options
+    let mut ssh_cmd = Command::new("ssh");
+    ssh_cmd
+        .arg("-o")
+        .arg("StrictHostKeyChecking=no")
+        .arg("-o")
+        .arg("BatchMode=yes")
+        .arg(format!("{}@{}", username, hostname))
+        .arg(command)
+        .stdout(Stdio::piped())
+        .stderr(Stdio::piped());
+
+    // Execute the command
+    let mut child = match ssh_cmd.spawn() {
+        Ok(child) => child,
+        Err(e) => return Err(format!("Failed to start SSH process: {}", e)),
+    };
+
+    // Capture and display stdout in real-time using a dedicated thread
+    let stdout = child.stdout.take().unwrap();
+    let display_name_stdout = display_name.clone();
+    let stdout_thread = thread::spawn(move || {
+        let reader = BufReader::new(stdout);
+        let prefix = format!("{}", "║".green());
+
+        for line in reader.lines() {
+            match line {
+                Ok(line) => println!(
+                    "{} {} {} {}",
+                    prefix,
+                    display_name_stdout.yellow(),
+                    prefix,
+                    line
+                ),
+                Err(_) => break,
+            }
+        }
+    });
+
+    // Capture and display stderr in real-time using a dedicated thread
+    let stderr = child.stderr.take().unwrap();
+    let display_name_stderr = display_name.clone();
+    let stderr_thread = thread::spawn(move || {
+        let reader = BufReader::new(stderr);
+        let prefix = format!("{}", "║".red());
+
+        for line in reader.lines() {
+            match line {
+                Ok(line) => println!(
+                    "{} {} {} {}",
+                    prefix,
+                    display_name_stderr.yellow(),
+                    prefix,
+                    line
+                ),
+                Err(_) => break,
+            }
+        }
+    });
+
+    // Wait for command to complete
+    let status = match child.wait() {
+        Ok(status) => status,
+        Err(e) => return Err(format!("Failed to wait for SSH process: {}", e)),
+    };
+
+    // Wait for stdout and stderr threads to complete
+    stdout_thread.join().unwrap();
+    stderr_thread.join().unwrap();
+
+    // Format exit code with color (green for success, red for failure)
+    let exit_code = status.code().unwrap_or(-1);
+    let code_string = if exit_code == 0 {
+        format!("{}", exit_code.to_string().green())
+    } else {
+        format!("{}", exit_code.to_string().red())
+    };
+
+    // Display completion message
+    println!(
+        "{} - COMPLETED (Exit code: [{}])",
+        display_name.yellow().bold(),
+        code_string
+    );
+
+    Ok(exit_code)
+}
+
+/// Execute commands on multiple hosts using the massh library (embedded SSH)
+///
+/// This function handles batch processing of hosts to maintain the original order
+/// while executing commands in parallel using the massh library.
+///
+/// # Arguments
+/// * `hosts` - Vector of (hostname, IP address, original index) tuples
+/// * `username` - SSH username
+/// * `command` - Command to execute
+/// * `parallel` - Maximum number of parallel connections
+/// * `code_only` - Whether to display only exit codes
+/// * `common_suffix` - Optional common suffix for hostname display formatting
+fn execute_with_massh(
+    hosts: &[(String, IpAddr, usize)],
+    username: &str,
+    command: &str,
+    parallel: i32,
+    code_only: bool,
+    common_suffix: &Option<String>,
+) {
+    // Create a lookup table for host data using IP addresses as keys
+    let mut hosts_and_ips: HashMap<IpAddr, (String, usize)> = HashMap::new();
+    let mut massh_hosts: Vec<MasshHostConfig> = Vec::new();
+
+    for (hostname, ip, idx) in hosts {
+        hosts_and_ips.insert(*ip, (hostname.clone(), *idx));
+        massh_hosts.push(MasshHostConfig {
+            addr: *ip,
+            auth: None,
+            port: None,
+            user: None,
+        });
+    }
+
+    // Process hosts in batches to respect parallelism setting while maintaining order
+    let batch_size = parallel as usize;
+    let mut processed = 0;
+
+    while processed < massh_hosts.len() {
+        let end = std::cmp::min(processed + batch_size, massh_hosts.len());
+
+        // Create a new config and vector for this batch
+        let mut batch_hosts = Vec::new();
+        for host in &massh_hosts[processed..end] {
+            batch_hosts.push(MasshHostConfig {
+                addr: host.addr,
+                auth: None,
+                port: None,
+                user: None,
+            });
+        }
+
+        // Create a new MasshClient for this batch with appropriate configuration
+        let batch_config = MasshConfig {
+            default_auth: SshAuth::Agent,
+            default_port: 22,
+            default_user: username.to_string(),
+            threads: batch_hosts.len() as u64,
+            timeout: 0,
+            hosts: batch_hosts,
+        };
+
+        let batch_massh = MasshClient::from(&batch_config);
+
+        // Execute the command on all hosts in this batch
+        let rx = batch_massh.execute(command.to_string());
+
+        // Collect all results from this batch before moving to the next
+        let mut batch_results = Vec::new();
+
+        while let Ok((host, result)) = rx.recv() {
+            // Extract IP address from the massh result
+            let ip: String = host.split('@').collect::<Vec<_>>()[1]
+                .split(':')
+                .collect::<Vec<_>>()[0]
+                .to_string();
+            let ip = ip.parse::<IpAddr>().unwrap();
+
+            // Lookup the original hostname and index
+            if let Some((hostname, idx)) = hosts_and_ips.get(&ip) {
+                batch_results.push((hostname.clone(), ip, result, *idx));
+            } else {
+                error!("Unexpected IP address in result: {}", ip);
+            }
+        }
+
+        // Sort results by original index to maintain consistent display order
+        batch_results.sort_by_key(|(_, _, _, idx)| *idx);
+
+        // Display results for each host in the batch
+        for (hostname, _ip, result, _) in batch_results {
+            let display_name = shorten_hostname(&hostname, common_suffix);
+
+            // Display hostname with consistent formatting
+            println!("\n{}", display_name.yellow().bold().to_string());
+
+            // Handle execution result
+            let output = match result {
+                Ok(output) => output,
+                Err(e) => {
+                    error!("Can't access server: {}", e);
+                    continue;
+                }
+            };
+
+            // Format exit code with color
+            let code_string = if output.exit_status == 0 {
+                format!("{}", output.exit_status.to_string().green())
+            } else {
+                format!("{}", output.exit_status.to_string().red())
+            };
+
+            // Display summary of command execution
+            println!(
+                "{}",
+                format!(
+                    "Exit code [{}] / stdout {} bytes / stderr {} bytes",
+                    code_string,
+                    output.stdout.len(),
+                    output.stderr.len()
+                )
+                .bold()
+            );
+
+            // Display command output if not in code-only mode
+            if !code_only {
+                // Display stdout with appropriate formatting
+                match String::from_utf8(output.stdout) {
+                    Ok(stdout) => match stdout.as_str() {
+                        "" => {}
+                        _ => {
+                            let prefix = if output.exit_status != 0 {
+                                format!("{}", "│".cyan())
+                            } else {
+                                format!("{}", "│".green())
+                            };
+                            for line in stdout.lines() {
+                                println!("{} {} - {}", prefix, display_name.yellow(), line);
+                            }
+                        }
+                    },
+                    Err(_) => {}
+                }
+                // Display stderr with appropriate formatting
+                match String::from_utf8(output.stderr) {
+                    Ok(stderr) => match stderr.as_str() {
+                        "" => {}
+                        _ => {
+                            for line in stderr.lines() {
+                                println!("{} {} - {}", "║".red(), display_name.yellow(), line);
+                            }
+                        }
+                    },
+                    Err(_) => {}
+                }
+            }
+        }
+
+        processed = end;
+    }
+}
+
+/// Main entry point for the application
 fn main() {
+    // Initialize logging with minimal formatting (no timestamp, no target)
     env_logger::Builder::from_env(Env::default().default_filter_or("info"))
         .format_timestamp(None)
         .format_target(false)
         .init();
+
+    // Parse command-line arguments
     let args = Args::parse();
 
+    // Build the list of target hosts based on user selection method
     let hosts = if args.known_hosts {
+        // Use regex pattern matching against known_hosts file
         info!("Using ~/.ssh/known_hosts to build server list.");
         let known_hosts = read_known_hosts();
         let mut all_hosts = Vec::new();
@@ -175,6 +585,7 @@ fn main() {
         }
         all_hosts
     } else {
+        // Use pattern expansion syntax (ranges and lists)
         info!("Using string expansion to build server list.");
         let mut all_hosts = Vec::new();
         for expression in args.expression.iter() {
@@ -183,12 +594,10 @@ fn main() {
         all_hosts
     };
 
-    // Dedup hosts from known_hosts file
+    // Remove duplicate hosts while preserving original order
     let matched_hosts: Vec<_> = hosts.into_iter().unique().collect();
 
-    // Build MasshHostConfig hostnames list
+    // Log parallelism setting if not using the default
-    let mut massh_hosts: Vec<MasshHostConfig> = vec![];
-    let mut hosts_and_ips: HashMap<IpAddr, String> = HashMap::new();
     if args.parallel != 100 {
         warn!("Parallelism: {} thread{}", &args.parallel, {
             if args.parallel != 1 {
@@ -199,125 +608,150 @@ fn main() {
         });
     }
 
-    info!("Matched hosts:");
+    // Store hosts with their original indices to preserve ordering
-    for host in matched_hosts.iter() {
+    let mut host_with_indices: Vec<(Host, usize)> = Vec::new();
-        let ip = match lookup_host(&host.name) {
+    for (idx, host) in matched_hosts.iter().enumerate() {
-            Ok(ip) => ip[0],
+        host_with_indices.push((host.clone(), idx));
-            Err(_) => {
-                error!("{} couldn't be resolved.", &host.name.red());
-                continue;
     }
-        };
-        info!("{} [{}]", &host.name, ip);
-        hosts_and_ips.insert(ip, host.name.clone());
-        massh_hosts.push(MasshHostConfig {
-            addr: ip,
-            auth: None,
-            port: None,
-            user: None,
-        })
-    }
-    // Build MasshConfig using massh_hosts vector
-    let config = MasshConfig {
-        default_auth: SshAuth::Agent,
-        default_port: 22,
-        default_user: args.username,
-        threads: args.parallel as u64,
-        timeout: 0,
-        hosts: massh_hosts,
-    };
-    let massh = MasshClient::from(&config);
 
-    // Ask for confirmation
+    info!("Matched hosts:");
-    if config.hosts.len() != 0
+
-        && (args.noconfirm == true
+    // Perform DNS resolution for all hosts in parallel
-            || match Question::new(&*format!(
+    // Results are stored with original indices to maintain order
+    let resolved_ips_with_indices = Arc::new(Mutex::new(Vec::<(String, IpAddr, usize)>::new()));
+
+    host_with_indices
+        .par_iter()
+        .for_each(|(host, idx)| match lookup_host(&host.name) {
+            Ok(ips) if !ips.is_empty() => {
+                let ip = ips[0];
+                let mut results = resolved_ips_with_indices.lock().unwrap();
+                results.push((host.name.clone(), ip, *idx));
+            }
+            Ok(_) => {
+                let mut results = resolved_ips_with_indices.lock().unwrap();
+                results.push((
+                    host.name.clone(),
+                    IpAddr::V4(std::net::Ipv4Addr::new(0, 0, 0, 0)),
+                    *idx,
+                ));
+            }
+            Err(_) => {
+                let mut results = resolved_ips_with_indices.lock().unwrap();
+                results.push((
+                    host.name.clone(),
+                    IpAddr::V4(std::net::Ipv4Addr::new(0, 0, 0, 0)),
+                    *idx,
+                ));
+            }
+        });
+
+    // Sort hosts by original index to maintain consistent display order
+    let mut resolved_hosts = resolved_ips_with_indices.lock().unwrap().clone();
+    resolved_hosts.sort_by_key(|(_, _, idx)| *idx);
+
+    // Display all matched hosts with their resolved IPs
+    for (hostname, ip, _) in &resolved_hosts {
+        if ip.is_unspecified() {
+            error!("DNS resolve failed: {}", hostname.red());
+        } else {
+            info!("{} [{}]", hostname, ip);
+        }
+    }
+
+    // Filter out hosts that couldn't be resolved
+    let valid_hosts: Vec<(String, IpAddr, usize)> = resolved_hosts
+        .into_iter()
+        .filter(|(_, ip, _)| !ip.is_unspecified())
+        .collect();
+
+    // Exit if no valid hosts remain
+    if valid_hosts.is_empty() {
+        error!("No valid hosts to connect to");
+        process::exit(1);
+    }
+
+    // Find common domain suffix to optimize display
+    let hostnames: Vec<String> = valid_hosts
+        .iter()
+        .map(|(hostname, _, _)| hostname.clone())
+        .collect();
+    let common_suffix = find_common_suffix(&hostnames);
+
+    // Inform user about display optimization if common suffix found
+    if let Some(suffix) = &common_suffix {
+        info!(
+            "Common domain suffix found: '{}' (will be displayed as '*')",
+            suffix
+        );
+    }
+
+    // Ask for confirmation before proceeding (unless --noconfirm is specified)
+    if !args.noconfirm
+        && match Question::new(&*format!(
             "Continue on following {} servers?",
-                &config.hosts.len()
+            &valid_hosts.len()
         ))
         .confirm()
         {
             Answer::YES => true,
-                Answer::NO => false,
+            Answer::NO => {
-                _ => unreachable!(),
-            })
-    {
-        info!("Run command on {} servers.", &config.hosts.len());
-
-        // Run a command on all the configured hosts.
-        // Receive the result of the command for each host and print its output.
-        let rx = massh.execute(args.command);
-
-        while let Ok((host, result)) = rx.recv() {
-            let ip: String = host.split('@').collect::<Vec<_>>()[1]
-                .split(':')
-                .collect::<Vec<_>>()[0]
-                .to_string();
-            let ip = ip.parse::<IpAddr>().unwrap();
-            println!(
-                "\n{}",
-                hosts_and_ips
-                    .get(&ip)
-                    .unwrap_or(&"Couldn't parse IP".to_string())
-                    .to_string()
-                    .yellow()
-                    .bold()
-                    .to_string()
-            );
-            let output = match result {
-                Ok(output) => output,
-                Err(e) => {
-                    error!("Can't access server: {}", e);
-                    continue;
-                }
-            };
-            let code_string = if output.exit_status == 0 {
-                format!("{}", output.exit_status.to_string().green())
-            } else {
-                format!("{}", output.exit_status.to_string().red())
-            };
-            println!(
-                "{}",
-                format!(
-                    "Exit code [{}] | std out/err [{}/{}] bytes",
-                    code_string,
-                    output.stdout.len(),
-                    output.stderr.len()
-                )
-                .bold()
-            );
-
-            if !args.code {
-                match String::from_utf8(output.stdout) {
-                    Ok(stdout) => match stdout.as_str() {
-                        "" => {}
-                        _ => {
-                            let prefix = if output.exit_status != 0 {
-                                format!("{}", "║".cyan())
-                            } else {
-                                format!("{}", "║".green())
-                            };
-                            for line in stdout.lines() {
-                                println!("{} {}", prefix, line);
-                            }
-                        }
-                    },
-                    Err(_) => {}
-                }
-                match String::from_utf8(output.stderr) {
-                    Ok(stderr) => match stderr.as_str() {
-                        "" => {}
-                        _ => {
-                            for line in stderr.lines() {
-                                println!("{} {}", "║".red(), line);
-                            }
-                        }
-                    },
-                    Err(_) => {}
-                }
-            }
-        }
-    } else {
                 warn!("Stopped");
+                process::exit(0);
+            }
+            _ => unreachable!(),
+        }
+    {
+        info!("Run command on {} servers.", &valid_hosts.len());
+    }
+
+    // Execute commands using selected method (system SSH or embedded library)
+    if !args.embedded_ssh {
+        // Use system SSH client (default behavior)
+        let batch_size = args.parallel as usize;
+        let mut processed = 0;
+
+        while processed < valid_hosts.len() {
+            let end = std::cmp::min(processed + batch_size, valid_hosts.len());
+            let batch = &valid_hosts[processed..end];
+
+            // Create a thread for each host in the current batch
+            let mut handles = Vec::new();
+
+            for (hostname, _, _) in batch {
+                let hostname = hostname.clone();
+                let username = args.username.clone();
+                let command = args.command.clone();
+                let common_suffix_clone = common_suffix.clone();
+
+                // Execute SSH command in a separate thread
+                let handle = thread::spawn(move || {
+                    match execute_ssh_command(&hostname, &username, &command, &common_suffix_clone)
+                    {
+                        Ok(_) => (),
+                        Err(e) => error!("Error executing command on {}: {}", hostname, e),
+                    }
+                });
+
+                handles.push(handle);
+            }
+
+            // Wait for all threads in this batch to complete
+            for handle in handles {
+                handle.join().unwrap();
+            }
+
+            processed = end;
+        }
+    } else {
+        // Use the embedded massh library implementation
+        execute_with_massh(
+            &valid_hosts,
+            &args.username,
+            &args.command,
+            args.parallel,
+            args.code,
+            &common_suffix,
+        );
     }
 }