For RHEL 6, RHEL 7, RHEL 8, RHEL 9
| RAM size | Recommended swap size | Recommended swap size if allowing for hibernation |
| From 0 to 2GB | 2 times the RAM size | 3 times the RAM size |
| From 2GB to 8GB | The same size of the RAM | 2 times the RAM size |
| From 8GB to 64GB | At least 4GB | 1.5 times the RAM size |
| From 64GB | At least 4GB | Hibernation is not recommended |
Note: A 100GB swap is recommended if system with over 140 logical processes or over 3TB RAM
https://access.redhat.com/solutions/15244
> /var/spool/mail/root（补充：这里以清空 root 用户的邮箱为例）
# rpm -qa | grep crash || yum install crash ; rpm -qa | grep kernel-debug || yum install kernel-debug# vim /etc/kdump.conf修改以下内容：
......
path /var/crash
......（
补充：
1) 默认的存放位置是 /var/crash
2) 把这里修改成想要存放内核崩溃信息的目录
3) 为了保险起见存放内核崩溃信息的位置最好有大于内存大小的剩余空间
）
# systemctl restart kdump ; systemctl enable kdump# systemctl status kdump（补充：当显示输出结果里包含 operational 或者 Active: active (exited) 时，则说明 Kdump 已经启用）
# vim /etc/sysctl.conf添加以下内容：
......
kernel.hung_task_panic=1# sysctl -p /etc/sysctl.conf（步骤略）
（
注意：
1) 只有 task hang 住，或者处理器线程 soft lock 时才会自动产生 dump
2) 此过程系统会自动重启
）
# vim /etc/sysctl.conf添加以下内容：
......
kernel.sysrq = 1# sysctl -p /etc/sysctl.conf同时先后按下以下三个按键：
ALT + PRINTSCREEN + C（
注意：
1) 此过程会让系统自动重启
2) 只是系统死机并不代表有 kernel panic
）
# vim /etc/sysctl.conf添加以下内容：
......
kernel.unknown_nmi_panic = 1
kernel.panic_on_unrecovered_nmi = 1
kernel.panic_on_io_nmi = 1# sysctl -p /etc/sysctl.conf（步骤略）
# echo c > /proc/sysrq-trigger（注意：此操作会造成系统重启）
参考文献：
https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/8/html/system_design_guide/installing-and-configuring-kdump_system-design-guide
https://access.redhat.com/solutions/916043
https://access.redhat.com/solutions/3698411
https://access.redhat.com/solutions/6038
https://access.redhat.com/solutions/23069
# iptables -nvL
Chain INPUT (policy ACCEPT 5 packets, 500 bytes)
......
Chain FORWARD (policy DROP 0 packets, 0 bytes)
......
Chain OUTPUT (policy DROP 1000 packets, 200K bytes)
......（
补充：
1) 这里的 policy ACCEPT 5 packets, 500 bytes 是指接收了 5 个数据包和 500 bytes 流量，ACCEPT 是指接收的状态
2) 这里的 policy DROP 1000 packets, 200K bytes 是指发出了 1000 数据包和 200K bytes 流量。DROP 是拒绝的状态
）
(Steps omitted)
$installedapps = get-AppxPackage
$aumidList = @()
foreach ($app in $installedapps)
{
foreach ($id in (Get-AppxPackageManifest $app).package.applications.application.id)
{
$aumidList += $app.packagefamilyname + "!" + $id
}
}
$aumidList
Microsoft.Windows.CloudExperienceHost_cw5n1h2txyewy!App
Microsoft.BioEnrollment_cw5n1h2txyewy!App
1527c705-839a-4832-9118-54d4Bd6a0c89_cw5n1h2txyewy!Microsoft.Windows.FilePicker
c5e2524a-ea46-4f67-841f-6a9465d9d515_cw5n1h2txyewy!App
E2A4F912-2574-4A75-9BB0-0D023378592B_cw5n1h2txyewy!Microsoft.Windows.AppResolverUX
Microsoft.LockApp_cw5n1h2txyewy!WindowsDefaultLockScreen
Microsoft.Win32WebViewHost_cw5n1h2txyewy!DPI.PerMonitorAware
Microsoft.Win32WebViewHost_cw5n1h2txyewy!DPI.SystemAware
Microsoft.Win32WebViewHost_cw5n1h2txyewy!DPI.Unaware
Microsoft.MicrosoftEdgeDevToolsClient_8wekyb3d8bbwe!App
Microsoft.Windows.ContentDeliveryManager_cw5n1h2txyewy!App
Microsoft.Windows.OOBENetworkCaptivePortal_cw5n1h2txyewy!App
Microsoft.Windows.NarratorQuickStart_8wekyb3d8bbwe!App
Microsoft.Windows.ParentalControls_cw5n1h2txyewy!App
Microsoft.Windows.PeopleExperienceHost_cw5n1h2txyewy!App
Microsoft.Windows.CallingShellApp_cw5n1h2txyewy!Microsoft.Windows.CallingShellApp
Microsoft.Windows.CapturePicker_cw5n1h2txyewy!App
NcsiUwpApp_8wekyb3d8bbwe!App
MicrosoftWindows.UndockedDevKit_cw5n1h2txyewy!App
Windows.CBSPreview_cw5n1h2txyewy!Microsoft.Windows.CBSPreview
Microsoft.Windows.XGpuEjectDialog_cw5n1h2txyewy!Microsoft.Windows.XGpuEjectDialog
Microsoft.Windows.StartMenuExperienceHost_cw5n1h2txyewy!App
Microsoft.Windows.SecHealthUI_cw5n1h2txyewy!SecHealthUI
Microsoft.AccountsControl_cw5n1h2txyewy!App
Microsoft.CredDialogHost_cw5n1h2txyewy!App
Microsoft.Windows.ShellExperienceHost_cw5n1h2txyewy!App
Microsoft.AAD.BrokerPlugin_cw5n1h2txyewy!App
Microsoft.Windows.OOBENetworkConnectionFlow_cw5n1h2txyewy!App
F46D4000-FD22-4DB4-AC8E-4E1DDDE828FE_cw5n1h2txyewy!App
Microsoft.XboxGameCallableUI_cw5n1h2txyewy!Microsoft.XboxGameCallableUI
Microsoft.AsyncTextService_8wekyb3d8bbwe!App
Microsoft.Windows.PinningConfirmationDialog_cw5n1h2txyewy!App
Windows.PrintDialog_cw5n1h2txyewy!Microsoft.Windows.PrintDialog
Microsoft.Windows.Apprep.ChxApp_cw5n1h2txyewy!App
windows.immersivecontrolpanel_cw5n1h2txyewy!microsoft.windows.immersivecontrolpanel
Microsoft.WindowsCamera_8wekyb3d8bbwe!App
Microsoft.Wallet_8wekyb3d8bbwe!App
RealtekSemiconductorCorp.RealtekAudioControl_dt26b99r8h8gj!App
Microsoft.GetHelp_8wekyb3d8bbwe!App
Microsoft.ECApp_8wekyb3d8bbwe!App
Microsoft.MicrosoftEdge.Stable_8wekyb3d8bbwe!App
Microsoft.MicrosoftPCManager_8wekyb3d8bbwe!App
Microsoft.MicrosoftPCManager_8wekyb3d8bbwe!PCWndManager
Microsoft.MicrosoftPCManager_8wekyb3d8bbwe!PCManagerService
Microsoft.ScreenSketch_8wekyb3d8bbwe!App
Microsoft.LanguageExperiencePackzh-CN_8wekyb3d8bbwe!App
Microsoft.LanguageExperiencePackzh-TW_8wekyb3d8bbwe!App
Microsoft.LanguageExperiencePacken-GB_8wekyb3d8bbwe!App
Clipchamp.Clipchamp_yxz26nhyzhsrt!App
Clipchamp.Clipchamp_yxz26nhyzhsrt!CLI
AppleInc.iTunes_nzyj5cx40ttqa!iTunes
AppleInc.iTunes_nzyj5cx40ttqa!AppleInc.Defaults
AppleInc.iTunes_nzyj5cx40ttqa!AppleInc.MDCrashReporter
Microsoft.HEIFImageExtension_8wekyb3d8bbwe!App
Microsoft.XboxGameOverlay_8wekyb3d8bbwe!App
Microsoft.XboxSpeechToTextOverlay_8wekyb3d8bbwe!App
Microsoft.Xbox.TCUI_8wekyb3d8bbwe!Microsoft.Xbox.TCUI
Microsoft.WebMediaExtensions_8wekyb3d8bbwe!Microsoft.WebMediaExtensions
Microsoft.XboxIdentityProvider_8wekyb3d8bbwe!Microsoft.XboxIdentityProvider
Microsoft.MicrosoftStickyNotes_8wekyb3d8bbwe!App
Microsoft.Getstarted_8wekyb3d8bbwe!App
Microsoft.ZuneVideo_8wekyb3d8bbwe!Microsoft.ZuneVideo
Microsoft.WindowsStore_8wekyb3d8bbwe!App
Microsoft.StorePurchaseApp_8wekyb3d8bbwe!App
Microsoft.VP9VideoExtensions_8wekyb3d8bbwe!App
Microsoft.Whiteboard_8wekyb3d8bbwe!Whiteboard
Microsoft.WebpImageExtension_8wekyb3d8bbwe!App
Microsoft.WindowsSoundRecorder_8wekyb3d8bbwe!App
Microsoft.XboxGamingOverlay_8wekyb3d8bbwe!App
Microsoft.Windows.Photos_8wekyb3d8bbwe!App
Microsoft.YourPhone_8wekyb3d8bbwe!App
Microsoft.DesktopAppInstaller_8wekyb3d8bbwe!App
Microsoft.DesktopAppInstaller_8wekyb3d8bbwe!PythonRedirector
Microsoft.DesktopAppInstaller_8wekyb3d8bbwe!winget
Microsoft.DesktopAppInstaller_8wekyb3d8bbwe!WinGetComServer
Microsoft.Windows.Search_cw5n1h2txyewy!CortanaUI
Microsoft.Windows.Search_cw5n1h2txyewy!ShellFeedsUI
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!PackageMetadata
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!Global.Accounts
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!Global.AppListBackup
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!Global.BackupBanner
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!Global.DesktopSpotlight
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!InputApp
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!Global.IrisService
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!Global.RulesEngine
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!ScreenClipping
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!WebExperienceHost
MicrosoftWindows.Client.CBS_cw5n1h2txyewy!WindowsBackup
AppleInc.iCloud_nzyj5cx40ttqa!iCloud
AppleInc.iCloud_nzyj5cx40ttqa!iCloudPhotoViewer
AppleInc.iCloud_nzyj5cx40ttqa!iCloudPasswords
AppleInc.iCloud_nzyj5cx40ttqa!iCloudChrome
AppleInc.iCloud_nzyj5cx40ttqa!iCloudPasswordsExtensionHelper
AppleInc.iCloud_nzyj5cx40ttqa!iCloudFirefox
AppleInc.iCloud_nzyj5cx40ttqa!eReporter
AppleInc.iCloud_nzyj5cx40ttqa!iCloudDrive
AppleInc.iCloud_nzyj5cx40ttqa!iCloudPhotos
AppleInc.iCloud_nzyj5cx40ttqa!ApplePhotoStreams
AppleInc.iCloud_nzyj5cx40ttqa!iCloudCKKS
AppleInc.iCloud_nzyj5cx40ttqa!APSDaemon
Microsoft.WindowsTerminal_8wekyb3d8bbwe!AppCreate a new bat file and create follow content:
start shell:Appsfolder\Microsoft.WindowsTerminal_8wekyb3d8bbwe!App(Add: taking starting the Terminal application as an example here)
(Steps omitted)
https://forum.rainmeter.net/viewtopic.php?t=22716