diff --git a/cmd/zfs_object_agent/Cargo.lock b/cmd/zfs_object_agent/Cargo.lock
index 761b07a4441e..ffb77e5bcae0 100644
--- a/cmd/zfs_object_agent/Cargo.lock
+++ b/cmd/zfs_object_agent/Cargo.lock
@@ -313,8 +313,8 @@ version = "0.20.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "51e3973b165dc0f435831a9e426de67e894de532754ff7a3f307c03ee5dec7dc"
 dependencies = [
- "clap",
- "heck",
+ "clap 2.34.0",
+ "heck 0.3.3",
  "indexmap",
  "log",
  "proc-macro2",
@@ -361,12 +361,42 @@ dependencies = [
  "ansi_term",
  "atty",
  "bitflags",
- "strsim",
- "textwrap",
+ "strsim 0.8.0",
+ "textwrap 0.11.0",
  "unicode-width",
  "vec_map",
 ]
 
+[[package]]
+name = "clap"
+version = "3.1.6"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "d8c93436c21e4698bacadf42917db28b23017027a4deccb35dbe47a7e7840123"
+dependencies = [
+ "atty",
+ "bitflags",
+ "clap_derive",
+ "indexmap",
+ "lazy_static",
+ "os_str_bytes",
+ "strsim 0.10.0",
+ "termcolor",
+ "textwrap 0.15.0",
+]
+
+[[package]]
+name = "clap_derive"
+version = "3.1.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "da95d038ede1a964ce99f49cbe27a7fb538d1da595e4b4f70b8c8f338d17bf16"
+dependencies = [
+ "heck 0.4.0",
+ "proc-macro-error",
+ "proc-macro2",
+ "quote",
+ "syn",
+]
+
 [[package]]
 name = "config"
 version = "0.12.0"
@@ -930,6 +960,12 @@ dependencies = [
  "unicode-segmentation",
 ]
 
+[[package]]
+name = "heck"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "2540771e65fc8cb83cd6e8a237f70c319bd5c29f78ed1084ba5d50eeac86f7f9"
+
 [[package]]
 name = "hermit-abi"
 version = "0.1.19"
@@ -1271,7 +1307,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1e7a3760cebfa88dc786e9a75654e01297b28a0ab28cd94e686a42f96823b9ff"
 dependencies = [
  "aspect-weave",
- "heck",
+ "heck 0.3.3",
  "indexmap",
  "proc-macro2",
  "quote",
@@ -1528,6 +1564,15 @@ dependencies = [
  "hashbrown 0.9.1",
 ]
 
+[[package]]
+name = "os_str_bytes"
+version = "6.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "8e22443d1643a904602595ba1cd8f7d896afe56d26712531c5ff73a15b2fbf64"
+dependencies = [
+ "memchr",
+]
+
 [[package]]
 name = "parking_lot"
 version = "0.11.2"
@@ -2283,6 +2328,12 @@ version = "0.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 
+[[package]]
+name = "strsim"
+version = "0.10.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "73473c0e59e6d5812c5dfe2a064a6444949f089e20eec9a2e5506596494e4623"
+
 [[package]]
 name = "subtle"
 version = "2.4.1"
@@ -2340,6 +2391,15 @@ dependencies = [
  "winapi 0.3.9",
 ]
 
+[[package]]
+name = "termcolor"
+version = "1.1.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "bab24d30b911b2376f3a13cc2cd443142f0c81dda04c118693e35b3835757755"
+dependencies = [
+ "winapi-util",
+]
+
 [[package]]
 name = "termion"
 version = "1.5.6"
@@ -2374,6 +2434,12 @@ dependencies = [
  "unicode-width",
 ]
 
+[[package]]
+name = "textwrap"
+version = "0.15.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b1141d4d61095b28419e22cb0bbf02755f5e54e0526f97f1e3d1d160e60885fb"
+
 [[package]]
 name = "thiserror"
 version = "1.0.30"
@@ -2739,6 +2805,15 @@ version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
 
+[[package]]
+name = "winapi-util"
+version = "0.1.5"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "70ec6ce85bb158151cae5e5c87f95a8e97d2c0c4b001223f33a334e3ce5de178"
+dependencies = [
+ "winapi 0.3.9",
+]
+
 [[package]]
 name = "winapi-x86_64-pc-windows-gnu"
 version = "0.4.0"
@@ -2810,7 +2885,7 @@ dependencies = [
  "anyhow",
  "async-trait",
  "chrono",
- "clap",
+ "clap 2.34.0",
  "exitcode",
  "log",
  "more-asserts",
@@ -2829,7 +2904,7 @@ name = "zcachedb"
 version = "0.1.0"
 dependencies = [
  "anyhow",
- "clap",
+ "clap 2.34.0",
  "exitcode",
  "git-version",
  "libc",
@@ -2933,7 +3008,7 @@ name = "zfs_object_agent"
 version = "0.1.0"
 dependencies = [
  "chrono",
- "clap",
+ "clap 2.34.0",
  "git-version",
  "lazy_static",
  "log",
@@ -2947,7 +3022,7 @@ dependencies = [
 name = "zfs_object_perf"
 version = "0.1.0"
 dependencies = [
- "clap",
+ "clap 2.34.0",
  "futures",
  "git-version",
  "log",
@@ -2986,7 +3061,7 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "chrono",
- "clap",
+ "clap 3.1.6",
  "futures",
  "git-version",
  "itertools",
diff --git a/cmd/zfs_object_agent/client/Cargo.toml b/cmd/zfs_object_agent/client/Cargo.toml
index 0977b2a37fbd..1897206b58d9 100644
--- a/cmd/zfs_object_agent/client/Cargo.toml
+++ b/cmd/zfs_object_agent/client/Cargo.toml
@@ -10,7 +10,7 @@ publish = false
 [dependencies]
 anyhow = "1.0"
 chrono = "0.4.19"
-clap = "2"
+clap = { version = "3.1.6", features = ["derive"] }
 futures = "0.3.13"
 git-version = "0.3.5"
 itertools = "0.10.3"
diff --git a/cmd/zfs_object_agent/client/src/main.rs b/cmd/zfs_object_agent/client/src/main.rs
index 1030c52bc35b..1c1d33b8e9d7 100644
--- a/cmd/zfs_object_agent/client/src/main.rs
+++ b/cmd/zfs_object_agent/client/src/main.rs
@@ -12,8 +12,8 @@ use ::util::writeln_stderr;
 use ::util::writeln_stdout;
 use chrono::prelude::*;
 use chrono::DateTime;
-use clap::Arg;
-use clap::SubCommand;
+use clap::Parser;
+use clap::Subcommand;
 use client::Client;
 use futures::stream::StreamExt;
 use git_version::git_version;
@@ -397,6 +397,42 @@ async fn do_destroy_old_pools(
     Ok(())
 }
 
+async fn do_dump_object(
+    object_access: Arc<ObjectAccess>,
+    pool_guid: u64,
+    object: u64,
+    verbose: usize,
+) {
+    match DataObject::get(
+        &object_access,
+        PoolGuid(pool_guid),
+        ObjectId::new(BlockId(object)),
+        ObjectAccessOpType::ReadsGet,
+        true,
+    )
+    .await
+    {
+        Ok(obj) => {
+            writeln_stdout!("Data object header: {}", obj);
+            for (k, v) in obj.blocks.iter().sorted() {
+                if verbose < 2 {
+                    writeln_stdout!(
+                        "Block id: {}, Length: {}, Contents: {:?}...",
+                        k,
+                        v.len(),
+                        v.slice(0..8)
+                    );
+                } else {
+                    writeln_stdout!("Block id: {}, Length: {}, Contents: {:?}", k, v.len(), v);
+                }
+            }
+        }
+        Err(e) => {
+            writeln_stderr!("Failed to access DataObject: {:?}", e);
+        }
+    };
+}
+
 fn get_object_access(
     endpoint: &str,
     region: &str,
@@ -419,227 +455,97 @@ fn get_object_access(
     }
 }
 
+#[derive(Parser)]
+//#[clap(long_about = None)]
+#[clap(version=GIT_VERSION)]
+#[clap(about = "ZFS Object Agent test")]
+#[clap(propagate_version = true)]
+struct Cli {
+    #[clap(short, long, help = "S3 endpoint", default_value = ENDPOINT)]
+    endpoint: String,
+    #[clap(short, long, help = "S3 region", default_value = REGION)]
+    region: String,
+    #[clap(short, long, help = "S3 bucket", default_value = BUCKET_NAME)]
+    bucket: String,
+    #[clap(short, long, help = "credentials profile", default_value = "default")]
+    profile: String,
+    #[clap(short = 'i', long, requires = "aws-secret-access-key")]
+    aws_access_key_id: Option<String>,
+    #[clap(short = 's', long, requires = "aws-access-key-id")]
+    aws_secret_access_key: Option<String>,
+    #[clap(short, long, parse(from_occurrences))]
+    verbose: usize,
+    #[clap(subcommand)]
+    command: Commands,
+}
+
+#[derive(Subcommand)]
+enum Commands {
+    S3Rusoto,
+    Create,
+    Write,
+    Read,
+    Free,
+    Btree,
+    Nvpair,
+    RusotoRole,
+    ListPools,
+    ListPoolObjects,
+    DestroyOldPools {
+        #[clap(short = 'd', long)]
+        days: u64,
+    },
+    DumpObject {
+        #[clap(short, long)]
+        pool_guid: u64,
+        #[clap(short, long)]
+        object: u64,
+    },
+}
+
 #[tokio::main]
-async fn main() {
-    let matches = clap::App::new("zoa_test")
-        .about("ZFS object agent test")
-        .version(GIT_VERSION)
-        .arg(
-            Arg::with_name("endpoint")
-                .short("e")
-                .long("endpoint")
-                .help("S3 endpoint")
-                .takes_value(true)
-                .default_value(ENDPOINT),
-        )
-        .arg(
-            Arg::with_name("region")
-                .short("r")
-                .long("region")
-                .help("S3 region")
-                .takes_value(true)
-                .default_value(REGION),
-        )
-        .arg(
-            Arg::with_name("bucket")
-                .short("b")
-                .long("bucket")
-                .help("S3 bucket")
-                .takes_value(true)
-                .default_value(BUCKET_NAME),
-        )
-        .arg(
-            Arg::with_name("profile")
-                .short("p")
-                .long("profile")
-                .help("credentials profile")
-                .takes_value(true)
-                .default_value("default"),
-        )
-        .arg(
-            Arg::with_name("aws_access_key_id")
-                .short("i")
-                .long("aws_access_key_id")
-                .takes_value(true)
-                .help("AWS access key id"),
-        )
-        .arg(
-            Arg::with_name("aws_secret_access_key")
-                .short("s")
-                .long("aws_secret_access_key")
-                .takes_value(true)
-                .help("AWS secret access key"),
-        )
-        .arg(
-            Arg::with_name("verbosity")
-                .short("v")
-                .long("verbose")
-                .help("verbosity")
-                .multiple(true),
-        )
-        .subcommand(SubCommand::with_name("s3").about("s3 test"))
-        .subcommand(SubCommand::with_name("s3_rusoto").about("s3 rusoto test"))
-        .subcommand(SubCommand::with_name("create").about("create test "))
-        .subcommand(SubCommand::with_name("write").about("write test"))
-        .subcommand(SubCommand::with_name("read").about("read test"))
-        .subcommand(SubCommand::with_name("free").about("free test"))
-        .subcommand(SubCommand::with_name("btree").about("btree test"))
-        .subcommand(SubCommand::with_name("nvpair").about("nvpair test"))
-        .subcommand(SubCommand::with_name("rusoto_role").about("rusoto credentials test"))
-        .subcommand(SubCommand::with_name("list_pools").about("list pools"))
-        .subcommand(SubCommand::with_name("list_pool_objects").about("list pool objects"))
-        .subcommand(
-            SubCommand::with_name("destroy_old_pools")
-                .about("destroy old pools")
-                .arg(
-                    Arg::with_name("number-of-days")
-                        .short("d")
-                        .long("number-of-days")
-                        .required(true)
-                        .takes_value(true)
-                        .help("number of days"),
-                ),
-        )
-        .subcommand(
-            SubCommand::with_name("dump_object")
-                .about("dump data object")
-                .arg(
-                    Arg::with_name("pool_guid")
-                        .short("p")
-                        .long("pool_guid")
-                        .required(true)
-                        .takes_value(true)
-                        .help("guid of pool to retrieve object from"),
-                )
-                .arg(
-                    Arg::with_name("object_id")
-                        .short("o")
-                        .long("object_id")
-                        .required(true)
-                        .takes_value(true)
-                        .help("id of object to retreive"),
-                ),
-        )
-        .get_matches();
-
-    // Command line parameters
-    let endpoint = matches.value_of("endpoint").unwrap();
-    let region_str = matches.value_of("region").unwrap();
-    let bucket_name = matches.value_of("bucket").unwrap();
-    let profile = matches.value_of("profile").unwrap();
-    let aws_access_key_id = matches.value_of("aws_access_key_id");
-    let aws_secret_access_key = matches.value_of("aws_secret_access_key");
-    let verbosity = matches.occurrences_of("verbosity");
-
-    if aws_access_key_id.is_some() != aws_secret_access_key.is_some() {
-        matches.usage();
-        panic!("Error: Both aws_access_key_id and aws_secret_access_key should be specified.");
-    }
+async fn main() -> Result<(), Box<dyn Error>> {
+    let cli = Cli::parse();
 
-    if verbosity > 0 || matches.subcommand_name().is_none() {
+    if cli.verbose > 0 {
         println!(
             "endpoint: {}, region: {}, bucket: {} profile: {} access_id: {:?}, secret_key: {:?}",
-            endpoint, region_str, bucket_name, profile, aws_access_key_id, aws_secret_access_key
+            cli.endpoint,
+            cli.region,
+            cli.bucket,
+            cli.profile,
+            cli.aws_access_key_id,
+            cli.aws_secret_access_key
         );
     }
 
     let object_access = get_object_access(
-        endpoint,
-        region_str,
-        bucket_name,
-        profile,
-        aws_access_key_id,
-        aws_secret_access_key,
+        &cli.endpoint,
+        &cli.region,
+        &cli.bucket,
+        &cli.profile,
+        cli.aws_access_key_id.as_deref(),
+        cli.aws_secret_access_key.as_deref(),
     );
 
-    match matches.subcommand() {
-        ("s3_rusoto", Some(_matches)) => {
-            do_s3_rusoto().await.unwrap();
-        }
-        ("create", Some(_matches)) => {
-            do_create().await.unwrap();
-        }
-        ("write", Some(_matches)) => {
-            do_write().await.unwrap();
-        }
-        ("read", Some(_matches)) => {
-            do_read().await.unwrap();
-        }
-        ("free", Some(_matches)) => {
-            do_free().await.unwrap();
-        }
-        ("btree", Some(_matches)) => {
-            do_btree();
-        }
-        ("nvpair", Some(_matches)) => {
-            do_nvpair();
-        }
-        ("rusoto_role", Some(_matches)) => {
-            do_rusoto_role().await.unwrap();
-        }
-        ("list_pools", Some(_matches)) => {
-            do_list_pools(&object_access, false).await.unwrap();
-        }
-        ("list_pool_objects", Some(_matches)) => {
-            do_list_pools(&object_access, true).await.unwrap();
-        }
-        ("destroy_old_pools", Some(destroy_matches)) => {
-            let age_str = destroy_matches.value_of("number-of-days").unwrap();
-            let min_age = Duration::from_secs(age_str.parse::<u64>().unwrap() * 60 * 60 * 24);
-
-            do_destroy_old_pools(&object_access, min_age).await.unwrap();
+    match cli.command {
+        Commands::S3Rusoto => do_s3_rusoto().await?,
+        Commands::Create => do_create().await?,
+        Commands::Write => do_write().await?,
+        Commands::Read => do_read().await?,
+        Commands::Free => do_free().await?,
+        Commands::Btree => do_btree(),
+        Commands::Nvpair => do_nvpair(),
+        Commands::RusotoRole => do_rusoto_role().await?,
+        Commands::ListPools => do_list_pools(&object_access, false).await?,
+        Commands::ListPoolObjects => do_list_pools(&object_access, true).await?,
+        Commands::DestroyOldPools { days } => {
+            let min_age = Duration::from_secs(days * 60 * 60 * 24);
+            do_destroy_old_pools(&object_access, min_age).await?;
         }
-        ("dump_object", Some(dump_matches)) => {
-            let pool_guid = match str::parse::<u64>(dump_matches.value_of("pool_guid").unwrap()) {
-                Ok(value) => PoolGuid(value),
-                Err(_e) => {
-                    writeln_stderr!("Failed to parse pool guid");
-                    return;
-                }
-            };
-            let object = match str::parse::<u64>(dump_matches.value_of("object_id").unwrap()) {
-                Ok(value) => ObjectId::new(BlockId(value)),
-                Err(_e) => {
-                    writeln_stderr!("Failed to parse object id");
-                    return;
-                }
-            };
-            match DataObject::get(
-                &object_access,
-                pool_guid,
-                object,
-                ObjectAccessOpType::ReadsGet,
-                true,
-            )
-            .await
-            {
-                Ok(obj) => {
-                    writeln_stdout!("Data object header: {}", obj);
-                    for (k, v) in obj.blocks.iter().sorted() {
-                        if verbosity < 2 {
-                            writeln_stdout!(
-                                "Block id: {}, Length: {}, Contents: {:?}...",
-                                k,
-                                v.len(),
-                                v.slice(0..8)
-                            );
-                        } else {
-                            writeln_stdout!(
-                                "Block id: {}, Length: {}, Contents: {:?}",
-                                k,
-                                v.len(),
-                                v
-                            );
-                        }
-                    }
-                }
-                Err(e) => {
-                    writeln_stderr!("Failed to access DataObject: {:?}", e);
-                }
-            };
+        Commands::DumpObject { pool_guid, object } => {
+            do_dump_object(object_access, pool_guid, object, cli.verbose).await
         }
-        _ => {
-            matches.usage();
-        }
-    };
+    }
+    Ok(())
 }