diff --git a/test/case/dhcp/server_host/test.py b/test/case/dhcp/server_host/test.py
index 73b6c8124..857042026 100755
--- a/test/case/dhcp/server_host/test.py
+++ b/test/case/dhcp/server_host/test.py
@@ -33,84 +33,84 @@
                                             lambda: env.attach("client2", "mgmt"))
 
     with test.step("Configure DHCP client and server DUTs"):
-        parallel(
-            lambda: server.put_config_dicts({
-                "ietf-interfaces": {
-                    "interfaces": {
-                        "interface": [
-                            {
-                                "name": server["link1"],
-                                "ipv4": {
-                                    "address": [{
-                                        "ip": "192.168.1.1",
-                                        "prefix-length": 24
-                                    }]
-                                }
-                            }, {
-                                "name": server["link2"],
-                                "ipv4": {
-                                    "address": [{
-                                        "ip": "192.168.2.1",
-                                        "prefix-length": 24
-                                    }]
-                                }
-                            },
-                        ]
-                    }
-                },
-                "infix-dhcp-server": {
-                    "dhcp-server": {
-                        "option": [{
-                            "id": "router", "address": "auto"
-                        }],
-                        "subnet": [
-                            {
-                                "subnet": "192.168.1.0/24",
-                                "pool": {
-                                    "start-address": POOL1,
-                                    "end-address":   POOL1
-                                },
-                                "host": [{
-                                    "address": ADDRESS1,
-                                    "match": {
-                                        "client-id": {"hex": HOSTCID1}
-                                    },
-                                    "option": [
-                                        {
-                                            "id": "hostname",
-                                            "name": HOSTNM11
-                                        }, {
-                                            "id": "classless-static-route",
-                                            "static-route": [{
-                                                "destination": "0.0.0.0/0",
-                                                "next-hop": GW1
-                                            }]
-                                        }
-                                    ]
+        server.put_config_dicts({
+            "ietf-interfaces": {
+                "interfaces": {
+                    "interface": [
+                        {
+                            "name": server["link1"],
+                            "ipv4": {
+                                "address": [{
+                                    "ip": "192.168.1.1",
+                                    "prefix-length": 24
                                 }]
-                            }, {
-                                "subnet": "192.168.2.0/24",
-                                "pool": {
-                                    "start-address": POOL2,
-                                    "end-address":   POOL2
-                                },
-                                "host": [{
-                                    "address": ADDRESS2,
-                                    "match": {
-                                        "client-id": {"str": HOSTCID2}
-                                    },
-                                    "option": [
-                                        {
-                                            "id": "hostname",
-                                            "name": HOSTNM22
-                                        }
-                                    ],
-                                    "lease-time": "infinite"
+                            }
+                        }, {
+                            "name": server["link2"],
+                            "ipv4": {
+                                "address": [{
+                                    "ip": "192.168.2.1",
+                                    "prefix-length": 24
                                 }]
+                            }
+                        },
+                    ]
+                }
+            },
+            "infix-dhcp-server": {
+                "dhcp-server": {
+                    "option": [{
+                        "id": "router", "address": "auto"
+                    }],
+                    "subnet": [
+                        {
+                            "subnet": "192.168.1.0/24",
+                            "pool": {
+                                "start-address": POOL1,
+                                "end-address":   POOL1
                             },
-                        ]
-                    }
-                }}),
+                            "host": [{
+                                "address": ADDRESS1,
+                                "match": {
+                                    "client-id": {"hex": HOSTCID1}
+                                },
+                                "option": [
+                                    {
+                                        "id": "hostname",
+                                        "name": HOSTNM11
+                                    }, {
+                                        "id": "classless-static-route",
+                                        "static-route": [{
+                                            "destination": "0.0.0.0/0",
+                                            "next-hop": GW1
+                                        }]
+                                    }
+                                ]
+                            }]
+                        }, {
+                            "subnet": "192.168.2.0/24",
+                            "pool": {
+                                "start-address": POOL2,
+                                "end-address":   POOL2
+                            },
+                            "host": [{
+                                "address": ADDRESS2,
+                                "match": {
+                                    "client-id": {"str": HOSTCID2}
+                                },
+                                "option": [
+                                    {
+                                        "id": "hostname",
+                                        "name": HOSTNM22
+                                    }
+                                ],
+                                "lease-time": "infinite"
+                            }]
+                        },
+                    ]
+                }
+            }})
+        parallel(
             # We request hostname option just to ensure we don't get it.
             lambda: client1.put_config_dicts({
                 "ietf-system": {
diff --git a/test/case/system/etc_default/test.py b/test/case/system/etc_default/test.py
index 6eb4c2818..610f5aaf1 100755
--- a/test/case/system/etc_default/test.py
+++ b/test/case/system/etc_default/test.py
@@ -7,6 +7,7 @@
 disabled, and that a file is removed when the entry is deleted.
 """
 import base64
+import subprocess
 
 import infamy
 from infamy.util import parallel
@@ -20,7 +21,8 @@ def content(text):
 
 
 def cat(tgtssh, name):
-    return tgtssh.runsh(f"cat /etc/default/{name}").stdout
+    return tgtssh.run_retry(f"cat /etc/default/{name}", text=True,
+                            stdout=subprocess.PIPE).stdout
 
 
 with infamy.Test() as test:
@@ -80,6 +82,6 @@ def cat(tgtssh, name):
         target.delete_xpath(f"/ietf-system:system/infix-system:advanced/defaults/default[name='{NEW}']")
 
     with test.step("Verify /etc/default/infamy-test is removed"):
-        assert tgtssh.runsh(f"test -e /etc/default/{NEW}").returncode != 0
+        assert tgtssh.run_retry(f"test -e /etc/default/{NEW}").returncode == 1
 
     test.succeed()
diff --git a/test/case/system/rc_d/test.py b/test/case/system/rc_d/test.py
index e9f67a320..504e86ba0 100755
--- a/test/case/system/rc_d/test.py
+++ b/test/case/system/rc_d/test.py
@@ -10,6 +10,7 @@
 and rebooting, the file must list the two names in configured order.
 """
 import base64
+import subprocess
 
 import infamy
 from infamy.util import parallel, wait_boot
@@ -63,7 +64,8 @@ def cleanup(env):
 
     with test.step("Verify scripts are extracted to /etc/rc.d in order"):
         tgtssh = env.attach("target", "mgmt", "ssh")
-        files = tgtssh.runsh("ls /etc/rc.d").stdout.split()
+        files = tgtssh.run_retry("ls /etc/rc.d", text=True,
+                                 stdout=subprocess.PIPE).stdout.split()
         assert files == ["01-first", "02-second"], f"unexpected /etc/rc.d contents: {files}"
 
     with test.step("Save to startup-config and reboot"):
@@ -77,10 +79,11 @@ def cleanup(env):
                                   lambda: env.attach("target", "mgmt", "ssh"))
 
     with test.step("Verify enabled scripts ran once, in order"):
-        out = tgtssh.runsh(f"cat {ORDER}").stdout.split()
+        out = tgtssh.run_retry(f"cat {ORDER}", text=True,
+                               stdout=subprocess.PIPE).stdout.split()
         assert out == ["first", "second"], f"unexpected run order: {out}"
 
     with test.step("Verify disabled script did not run"):
-        assert tgtssh.runsh(f"test -e {NEVER}").returncode != 0, "disabled script was run"
+        assert tgtssh.run_retry(f"test -e {NEVER}").returncode == 1, "disabled script was run"
 
     test.succeed()