NFS/トラブルシューティング - 版の履歴

Kusakata: 同期

2017-11-06T11:55:28Z

同期

← 古い版		2017年11月6日 (月) 20:55時点における版
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	[[Category:ネットワーク]]		[[Category:ネットワーク共有]]
	[[ar:NFS]]		[[ar:NFS]]
	[[de:Network File System]]		[[de:Network File System]]
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	=== mount.nfs: Operation not permitted ===		=== mount.nfs: Operation not permitted ===

			==== NFSv4 ====
			[[Kerberos]] (sec=krb5*) を使用している場合、クライアントとサーバーの時刻が正しいことを確認してください。[[Network Time Protocol daemon\|ntpd]] または [[systemd-timesyncd]] を使用することを推奨します。

			==== NFSv3 以前 ====
	''nfs-utils'' 1.2.1-2 以上にアップデートすると、NFS 共有のマウントは機能を停止します。''nfs-utils'' がデフォルトで NFSv3 ではなく NFSv4 を使うようになるからです。この問題はコマンドラインでマウントオプションとして {{ic\|1='vers=3'}} や {{ic\|1='nfsvers=3'}} を使うことで解決できます:		''nfs-utils'' 1.2.1-2 以上にアップデートすると、NFS 共有のマウントは機能を停止します。''nfs-utils'' がデフォルトで NFSv3 ではなく NFSv4 を使うようになるからです。この問題はコマンドラインでマウントオプションとして {{ic\|1='vers=3'}} や {{ic\|1='nfsvers=3'}} を使うことで解決できます:
	# mount.nfs ''remote target'' ''directory'' -o ...,vers=3,...		# mount.nfs ''remote target'' ''directory'' -o ...,vers=3,...
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	}}		}}

			{{ic\|retrans}} カラムが 0 よりも大きい場合、サーバーが NFS リクエストに応答できてないので、スレッド数を増やす必要があります。
	If the {{ic\|retrans}} column contains a number larger than 0, the server is failing to respond to some NFS requests, and the number of threads should be increased.

			サーバーのスレッド数を増やすには、{{ic\|/etc/nfs.conf}} ファイルを編集して {{ic\|[server] threads}} 変数の値を設定してください。
	To increase the number of threads on the server, edit the file {{ic\|/etc/conf.d/nfs-server.conf}} and set the value in the {{ic\|NFSD_OPTS}} variable.

	For example, to set the number of threads to 32:
			デフォルトのスレッド数は 8 です。{{ic\|retrans}} が常に 0 になるまで数字を倍加させてみてください。数字を大きくすることに心配する必要はありません。負担によってはスレッド数を 256 にまで増やしても特に不思議ではありません。設定ファイルを編集したら NFS サーバーを再起動してください。クライアントの統計情報はクライアントを再起動しないとゼロにリセットされないので注意してください。
	{{hc\|/etc/conf.d/nfs-server.conf\|
	NFSD_OPTS="32"
	}}

	~~The~~ ~~default~~ number of threads is 8. ~~Try~~ ~~doubling~~ ~~this~~ ~~number~~ ~~until~~ {{ic\|~~retrans~~}} ~~remains~~ ~~consistently~~ at ~~zero. Don't be afraid of increasing~~ the ~~number quite substantially. 256~~ threads ~~may be quite reasonable~~, ~~depending on~~ the ~~workload.~~ ~~You~~ ~~will~~ ~~need~~ to ~~restart~~ ~~the~~ NFS ~~server~~ daemon ~~each~~ ~~time~~ ~~you~~ ~~modify~~ the ~~configuration~~ ~~file.~~ ~~Bear~~ in ~~mind~~ ~~that~~ the ~~client~~ ~~statistics will only be reset~~ to ~~zero when the client is~~ ~~rebooted~~.		While the number of threads can be increased at runtime via an echo to {{ic\|/proc/fs/nfsd/threads}}, the cache size (double the threads, see the '''ra''' line of /proc/net/rpc/nfsd) is not dynamic. The NFS daemon must be restarted with the new thread size during initialization in order for the thread cache to properly adjust.

	Use '''htop''' (disable the hiding of kernel threads) to keep an eye on how much work each nfsd thread is doing. If you reach a point where the {{ic\|retrans}} values are non-zero, but you can see {{ic\|nfsd}} threads on the server doing no work, something different is now causing your bottleneck, and you'll need to re-diagnose this new problem.		Use '''htop''' (disable the hiding of kernel threads) to keep an eye on how much work each nfsd thread is doing. If you reach a point where the {{ic\|retrans}} values are non-zero, but you can see {{ic\|nfsd}} threads on the server doing no work, something different is now causing your bottleneck, and you'll need to re-diagnose this new problem.
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	#define RPCDBG_ALL 0x7fff		#define RPCDBG_ALL 0x7fff
	}}		}}

	=== 一般注記事項 ===
	* While the number of threads can be increased at runtime via an echo to {{ic\|/proc/fs/nfsd/threads}}, the cache size (double the threads, see the '''ra''' line of /proc/net/rpc/nfsd) is not dynamic. The NFS daemon must be restarted with the new thread size during initialization in order for the thread cache to properly adjust.

	=== 参照 ===		=== 参照 ===
	* [https://github.com/torvalds/linux/tree/master/include/linux https://github.com/torvalds/linux/tree/master/include/linux]		* [https://github.com/torvalds/linux/tree/master/include/linux https://github.com/torvalds/linux/tree/master/include/linux]
			* {{man\|8\|rpcdebug}}
	* [http://linux.die.net/man/8/rpcdebug http://linux.die.net/man/8/rpcdebug]
	* [http://utcc.utoronto.ca/~cks/space/blog/linux/NFSClientDebuggingBits http://utcc.utoronto.ca/~cks/space/blog/linux/NFSClientDebuggingBits]		* [http://utcc.utoronto.ca/~cks/space/blog/linux/NFSClientDebuggingBits http://utcc.utoronto.ca/~cks/space/blog/linux/NFSClientDebuggingBits]
	* [http://www.novell.com/support/kb/doc.php?id=7011571 http://www.novell.com/support/kb/doc.php?id=7011571]		* [http://www.novell.com/support/kb/doc.php?id=7011571 http://www.novell.com/support/kb/doc.php?id=7011571]

2017年7月21日 (金) 12:04にToMeWelcomeによる

2017-07-21T12:04:32Z

← 古い版		2017年7月21日 (金) 21:04時点における版
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	{{ic\|nfs-client.target}} を[[起動]]・[[有効化]]してサーバー上で適切なデーモン (nfs-idmapd や rpc-gssd など) が動作していることを確認してください。		{{ic\|nfs-client.target}} を[[起動]]・[[有効化]]してサーバー上で適切なデーモン (nfs-idmapd や rpc-gssd など) が動作していることを確認してください。

	=== ~~OS X~~ クライアントから接続できない ===		=== macOS クライアントから接続できない ===

	~~OS X~~ クライアントから接続したときに、サーバーのログでは問題ないようにみえるのに、~~OS X~~ が NFS 共有のマウントを拒否することがあります。以下の方法で解決できます:		macOS クライアントから接続したときに、サーバーのログでは問題ないようにみえるのに、macOS が NFS 共有のマウントを拒否することがあります。以下の方法で解決できます:

	* NFS サーバーで、{{ic\|/etc/exports}} を編集して {{ic\|insecure}} オプションを追加して {{ic\|exportfs -r}} を再実行する。		* NFS サーバーで、{{ic\|/etc/exports}} を編集して {{ic\|insecure}} オプションを追加して {{ic\|exportfs -r}} を再実行する。

	* ~~OS X~~ クライアントで、{{ic\|mount}} コマンドに {{ic\|resvport}} オプションを追加する。{{ic\|/etc/nfs.conf}} でデフォルトのクライアントマウントオプションとして {{ic\|resvport}} を設定することもできます:		* macOS クライアントで、{{ic\|mount}} コマンドに {{ic\|resvport}} オプションを追加する。{{ic\|/etc/nfs.conf}} でデフォルトのクライアントマウントオプションとして {{ic\|resvport}} を設定することもできます:

	{{hc\|/etc/nfs.conf\|		{{hc\|/etc/nfs.conf\|
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	デフォルトのクライアントマウントオプションを変更すると Finder から "Connect to Server..." で共有をマウントする場合にも影響します。		デフォルトのクライアントマウントオプションを変更すると Finder から "Connect to Server..." で共有をマウントする場合にも影響します。

	=== ~~OS X~~ クライアントからの接続が不安定 ===		=== macOS クライアントからの接続が不安定 ===

	~~OS X~~ の NFS クライアントは ~~OS X~~ サーバーに最適化されているため Linux サーバーでは複数の問題が存在します。パフォーマンスが出なかったり、頻繁に切断したり、日本語の文字に問題が起こる場合、デフォルトのマウントオプションを編集して Mac クライアントの {{ic\|/etc/nfs.conf}} に {{ic\|<nowiki>nfs.client.mount.options = intr,locallocks,nfc</nowiki>}} という行を追加してください。マウントオプションに関する詳細情報は [https://developer.apple.com/legacy/library/documentation/Darwin/Reference/ManPages/man8/mount_nfs.8.html こちら] にあります。		macOS の NFS クライアントは macOS サーバーに最適化されているため Linux サーバーでは複数の問題が存在します。パフォーマンスが出なかったり、頻繁に切断したり、日本語の文字に問題が起こる場合、デフォルトのマウントオプションを編集して Mac クライアントの {{ic\|/etc/nfs.conf}} に {{ic\|<nowiki>nfs.client.mount.options = intr,locallocks,nfc</nowiki>}} という行を追加してください。マウントオプションに関する詳細情報は [https://developer.apple.com/legacy/library/documentation/Darwin/Reference/ManPages/man8/mount_nfs.8.html こちら] にあります。

	=== 巨大なファイルをコピーするときにクライアントが一時的にフリーズする ===		=== 巨大なファイルをコピーするときにクライアントが一時的にフリーズする ===

Kusakata: 同期

2017-06-17T13:57:55Z

同期

差分を表示

Kusakata: 文字列「[[zh-CN:」を「[[zh-hans:」に置換

2017-01-28T15:35:27Z

文字列「[[zh-CN:」を「[[zh-hans:」に置換

← 古い版		2017年1月29日 (日) 00:35時点における版
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	[[fr:NFS]]		[[fr:NFS]]
	[[it:NFSv4]]		[[it:NFSv4]]
	[[zh-CN:NFS]]		[[zh-hans:NFS]]
	{{Related articles start}}		{{Related articles start}}
	{{Related\|NFS}}		{{Related\|NFS}}

Kusakata: 同期

2016-03-08T05:08:27Z

同期

← 古い版		2016年3月8日 (火) 14:08時点における版
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	When trying to connect from a OS X client, you will see that everything is ok at logs, but MacOS X refuses to mount your NFS share. You have to add {{ic\|insecure}} option to your share and re-run {{ic\|exportfs -r}}.		When trying to connect from a OS X client, you will see that everything is ok at logs, but MacOS X refuses to mount your NFS share. You have to add {{ic\|insecure}} option to your share and re-run {{ic\|exportfs -r}}.

			=== OS X クライアントからの接続が不安定 ===
	=== Unreliable connection from OS X clients ===

	OS X's NFS ~~client is optimized for~~ OS X ~~Servers~~ ~~and~~ ~~might~~ ~~present~~ ~~some~~ ~~issues with Linux servers~~. ~~If you are experiencing slow performance, frequent disconnects and problems with international characters edit the default mount options by adding the line~~ {{ic\|<nowiki>nfs.client.mount.options = intr,locallocks,nfc</nowiki>}} ~~to {{ic\|/etc/nfs.conf}} on your Mac client. More information about the mount options can be found~~ [https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man8/mount_nfs.8.html#//apple_ref/doc/man/8/mount_nfs ~~here~~].		OS X の NFS クライアントは OS X サーバーに最適化されているため Linux サーバーでは複数の問題が存在します。パフォーマンスが出なかったり、頻繁に切断したり、日本語の文字に問題が起こる場合、デフォルトのマウントオプションを編集して Mac クライアントの {{ic\|/etc/nfs.conf}} に {{ic\|<nowiki>nfs.client.mount.options = intr,locallocks,nfc</nowiki>}} という行を追加してください。マウントオプションに関する詳細情報は [https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man8/mount_nfs.8.html#//apple_ref/doc/man/8/mount_nfs こちら] にあります。

			=== 巨大なファイルをコピーするときにクライアントが一時的にフリーズする ===
	=== Intermittent client freezes when copying large files ===

			クライアントマシンから NFS サーバーに巨大なファイルをコピーする際、転送速度に非常に高速だと、数秒後に速度が落ちて、転送が完了するまで暫くの間、クライアントマシンが一時的にロックアップすることがあります。
	If you copy large files from your client machine to the NFS server, the transfer speed is ''very'' fast, but after some seconds the speed drops and your client machine intermittently locks up completely for some time until the transfer is finished.

			クライアントの ({{ic\|/etc/fstab}} の) マウントオプションに {{ic\|sync}} を追加することで問題は解決します。
	Try adding <tt>sync</tt> as a mount option on the client (e.g. in <tt>/etc/fstab</tt>) to fix this problem.

	=== mount.nfs: Operation not permitted ===		=== mount.nfs: Operation not permitted ===

	~~After updating to~~ ''nfs-utils'' 1.2.1-2 ~~or higher, mounting~~ NFS ~~shares stopped working. Henceforth,~~ ''nfs-utils'' ~~uses NFSv4 per default instead of~~ NFSv3. ~~The~~ ~~problem~~ ~~can be solved by using either mount option~~ {{ic\|1='vers=3'}} or {{ic\|1='nfsvers=3'}} ~~on the command line~~:		''nfs-utils'' 1.2.1-2 以上にアップデートすると、NFS 共有のマウントは機能を停止します。''nfs-utils'' がデフォルトで NFSv3 ではなく NFSv4 を使うようになるからです。この問題はコマンドラインでマウントオプションとして {{ic\|1='vers=3'}} や {{ic\|1='nfsvers=3'}} を使うことで解決できます:
	# mount.nfs ''remote target'' ''directory'' -o ...,vers=3,...		# mount.nfs ''remote target'' ''directory'' -o ...,vers=3,...
	# mount.nfs ''remote target'' ''directory'' -o ...,nfsvers=3,...		# mount.nfs ''remote target'' ''directory'' -o ...,nfsvers=3,...
	~~or in~~ {{ic\|/etc/fstab}}:		もしくは {{ic\|/etc/fstab}} でマウントする場合:
	''remote target'' ''directory'' nfs ...,vers=3,... 0 0		''remote target'' ''directory'' nfs ...,vers=3,... 0 0
	''remote target'' ''directory'' nfs ...,nfsvers=3,... 0 0		''remote target'' ''directory'' nfs ...,nfsvers=3,... 0 0

			=== mount.nfs: Protocol not supported ===

			Check you are not mounting including the export root.
			Use:
			# mount SERVER:/ /mnt
			instead of, i.e.:
			# mount SERVER:/srv/nfs4/ /mnt

			Sometimes it could be the same problem with "Operation not permitted" : ''nfs-utils'' uses NFSv4 per default instead of NFSv3. Go and see the previons section

			=== Vagrant と synced_folders の問題 ===

			Vagrant のスクリプトで NFS を通してフォルダをマウントできない場合、{{Pkg\|net-tools}} パッケージをインストールすることで問題は解決します。

	== パフォーマンスの問題 ==		== パフォーマンスの問題 ==
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	It is possible to change the MTU of many network cards. If your clients are on a separate subnet (e.g. for a Beowulf cluster), it may be safe to configure all of the network cards to use a high MTU. This should be done in very-high-bandwidth environments.		It is possible to change the MTU of many network cards. If your clients are on a separate subnet (e.g. for a Beowulf cluster), it may be safe to configure all of the network cards to use a high MTU. This should be done in very-high-bandwidth environments.

			'''rsize''' と '''wsize''' についての詳細は '''nfs''' の man ページを参照してください。
	See also the '''nfs''' manual page for more about '''rsize''' and '''wsize'''.


	== デバッグ ==		== デバッグ ==
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	\|}		\|}

			'''-m''' オプションでは、以下のモジュールが利用できます:
	For the '''-m''' option, the available modules are:

	{\| class="wikitable"		{\| class="wikitable"
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	! モジュール !! 説明		! モジュール !! 説明
	\|-		\|-
	\| nfsd \|\| ~~The~~ NFS ~~server~~		\| nfsd \|\| NFS サーバー
	\|-		\|-
	\| nfs \|\| ~~The~~ NFS ~~client~~		\| nfs \|\| NFS クライアント
	\|-		\|-
	\| nlm \|\| ~~The~~ Network Lock Manager~~, in either an NFS client or server~~		\| nlm \|\| NFS クライアントあるいはサーバーの Network Lock Manager
	\|-		\|-
	\| rpc \|\| ~~The~~ Remote Procedure Call ~~module, in either an NFS client or server~~		\| rpc \|\| NFS クライアントあるいはサーバーの Remote Procedure Call モジュール
	\|}		\|}

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	If nfs-idmapd.service refuses to start because it cannot open the Pipefs-directory (defined in /etc/idmapd.conf and appended with '/nfs'), issue a mkdir-command and restart the daemon.		If nfs-idmapd.service refuses to start because it cannot open the Pipefs-directory (defined in /etc/idmapd.conf and appended with '/nfs'), issue a mkdir-command and restart the daemon.

	詳しくは [[NFS#ID マッピング]] を参照してください。

Kusakata: 訳追加

2015-03-10T15:50:14Z

訳追加

← 古い版		2015年3月11日 (水) 00:50時点における版
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	=== exportfs: /etc/exports:2: syntax error: bad option list ===		=== exportfs: /etc/exports:2: syntax error: bad option list ===

			{{ic\|/etc/exports}} 内のオプションリストから空白を全て削除してください。
	Delete all space from the option list in {{ic\|/etc/exports}}

	=== ~~Group~~/GID ~~permissions issues~~ ===		=== グループ/GID パーミッションの問題 ===

	If NFS shares mount fine, and are fully accessible to the owner, but not to group members; check the number of groups that user belongs to. NFS has a limit of 16 on the number of groups a user can belong to. If you have users with more than this, you need to enable the {{ic\|--manage-gids}} start-up flag for {{ic\|rpc.mountd}} on the NFS server.		If NFS shares mount fine, and are fully accessible to the owner, but not to group members; check the number of groups that user belongs to. NFS has a limit of 16 on the number of groups a user can belong to. If you have users with more than this, you need to enable the {{ic\|--manage-gids}} start-up flag for {{ic\|rpc.mountd}} on the NFS server.
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	}}		}}

	=== "Permission denied" ~~when trying to write files~~ ===		=== ファイルを書き込もうとしたときに "Permission denied" ===

			* root で共有をマウントして、クライアントから完全に読み書きできるようにしたい場合、{{ic\|/etc/exports}} のエクスポートに no_root_squash オプションを追加してください:
	* If you need to mount shares as root, and have full r/w access from the client, add the no_root_squash option to the export in {{ic\|/etc/exports}}:
	/var/cache/pacman/pkg 192.168.1.0/24(rw,no_subtree_check,no_root_squash)		/var/cache/pacman/pkg 192.168.1.0/24(rw,no_subtree_check,no_root_squash)

	=== "RPC: Program not registered" ~~when showmount -e command issued~~ ===		=== showmount -e コマンドを実行したときに "RPC: Program not registered" ===

	~~Make sure that~~ {{ic\|nfs-server.service}} ~~and~~ {{ic\|rpcbind.service}} ~~are running on the server site, see~~ [[systemd]]. ~~If they are not, start and enable them.~~		サーバー側で {{ic\|nfs-server.service}} と {{ic\|rpcbind.service}} が実行していることを確認してください。[[systemd]] を参照。実行されてない場合、サービスを起動して有効化してください。

	== クライアント側の問題 ==		== クライアント側の問題 ==
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	=== mount.nfs4: No such device ===		=== mount.nfs4: No such device ===

			{{ic\|nfs}} モジュールがロードされているか確認してください:
	Check that you have loaded the {{ic\|nfs}} module
	lsmod \| grep nfs		lsmod \| grep nfs
			上記コマンドで何も返ってこなかったり nfsd-stuff しか表示されない場合、次を実行:
	and if previous returns empty or only nfsd-stuff, do
	# modprobe nfs		# modprobe nfs

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	== パフォーマンスの問題 ==		== パフォーマンスの問題 ==

	~~This~~ [http://nfs.sourceforge.net/nfs-howto/ar01s05.html NFS Howto ~~page~~] ~~has some useful information regarding performance. Here are some further tips~~:		この [http://nfs.sourceforge.net/nfs-howto/ar01s05.html NFS Howto ページ] にパフォーマンスに関する有益な情報が載っています。以下はその他のヒントです:

	=== 問題の診断 ===		=== 問題の診断 ===
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	{\| class="wikitable"		{\| class="wikitable"
	\|-		\|-
			! オプション !! 説明
	! Option !! Description
	\|-		\|-
	\| -c \|\| Clear the given debug flags		\| -c \|\| Clear the given debug flags
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	{\| class="wikitable"		{\| class="wikitable"
	\|-		\|-
			! モジュール !! 説明
	! Module !! Description
	\|-		\|-
	\| nfsd \|\| The NFS server		\| nfsd \|\| The NFS server
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	\|}		\|}

			例:
	Examples:
	{{bc\|		{{bc\|
	rpcdebug -m rpc -s all # sets all debug flags for RPC		rpcdebug -m rpc -s all # sets all debug flags for RPC

Kusakata: ページの作成:「Category:ネットワーク ar:NFS de:Network File System en:NFS/Troubleshooting es:NFS fr:NFS it:NFSv4 zh-CN:NFS {{Related articles start...」

2015-02-15T05:58:34Z

ページの作成:「Category:ネットワーク ar:NFS de:Network File System en:NFS/Troubleshooting es:NFS fr:NFS it:NFSv4 zh-CN:NFS {{Related articles start...」

新規ページ

[[Category:ネットワーク]]
[[ar:NFS]]
[[de:Network File System]]
[[en:NFS/Troubleshooting]]
[[es:NFS]]
[[fr:NFS]]
[[it:NFSv4]]
[[zh-CN:NFS]]
{{Related articles start}}
{{Related|NFS}}
{{Related articles end}}

よくある問題と解決法の記事。

== サーバー側の問題 ==

=== exportfs: /etc/exports:2: syntax error: bad option list ===

Delete all space from the option list in {{ic|/etc/exports}}

=== Group/GID permissions issues ===

If NFS shares mount fine, and are fully accessible to the owner, but not to group members; check the number of groups that user belongs to. NFS has a limit of 16 on the number of groups a user can belong to. If you have users with more than this, you need to enable the {{ic|--manage-gids}} start-up flag for {{ic|rpc.mountd}} on the NFS server.

{{hc|/etc/conf.d/nfs-server.conf|2=
# Options for rpc.mountd.
# If you have a port-based firewall, you might want to set up
# a fixed port here using the --port option.
# See rpc.mountd(8) for more details.

MOUNTD_OPTS="--manage-gids"
}}

=== "Permission denied" when trying to write files ===

* If you need to mount shares as root, and have full r/w access from the client, add the no_root_squash option to the export in {{ic|/etc/exports}}:
/var/cache/pacman/pkg 192.168.1.0/24(rw,no_subtree_check,no_root_squash)

=== "RPC: Program not registered" when showmount -e command issued ===

Make sure that {{ic|nfs-server.service}} and {{ic|rpcbind.service}} are running on the server site, see [[systemd]]. If they are not, start and enable them.

== クライアント側の問題 ==

=== mount.nfs4: No such device ===

Check that you have loaded the {{ic|nfs}} module
lsmod | grep nfs
and if previous returns empty or only nfsd-stuff, do
# modprobe nfs

=== mount.nfs4: access denied by server while mounting ===

NFS shares have to reside in /srv - check your {{ic|/etc/exports}} file and if necessary create the proper folder structure as described in the [[NFS#File_system]] page.

Check that the permissions on your client's folder are correct. Try using 755.

or try "exportfs -rav" reload {{ic|/etc/exports}} file.

=== OS X クライアントから接続できない ===

When trying to connect from a OS X client, you will see that everything is ok at logs, but MacOS X refuses to mount your NFS share. You have to add {{ic|insecure}} option to your share and re-run {{ic|exportfs -r}}.

=== Unreliable connection from OS X clients ===

OS X's NFS client is optimized for OS X Servers and might present some issues with Linux servers. If you are experiencing slow performance, frequent disconnects and problems with international characters edit the default mount options by adding the line {{ic|<nowiki>nfs.client.mount.options = intr,locallocks,nfc</nowiki>}} to {{ic|/etc/nfs.conf}} on your Mac client. More information about the mount options can be found [https://developer.apple.com/library/mac/#documentation/Darwin/Reference/ManPages/man8/mount_nfs.8.html#//apple_ref/doc/man/8/mount_nfs here].

=== Intermittent client freezes when copying large files ===

If you copy large files from your client machine to the NFS server, the transfer speed is ''very'' fast, but after some seconds the speed drops and your client machine intermittently locks up completely for some time until the transfer is finished.

Try adding <tt>sync</tt> as a mount option on the client (e.g. in <tt>/etc/fstab</tt>) to fix this problem.

=== mount.nfs: Operation not permitted ===

After updating to ''nfs-utils'' 1.2.1-2 or higher, mounting NFS shares stopped working. Henceforth, ''nfs-utils'' uses NFSv4 per default instead of NFSv3. The problem can be solved by using either mount option {{ic|1='vers=3'}} or {{ic|1='nfsvers=3'}} on the command line:
# mount.nfs ''remote target'' ''directory'' -o ...,vers=3,...
# mount.nfs ''remote target'' ''directory'' -o ...,nfsvers=3,...
or in {{ic|/etc/fstab}}:
''remote target'' ''directory'' nfs ...,vers=3,... 0 0
''remote target'' ''directory'' nfs ...,nfsvers=3,... 0 0

== パフォーマンスの問題 ==

This [http://nfs.sourceforge.net/nfs-howto/ar01s05.html NFS Howto page] has some useful information regarding performance. Here are some further tips:

=== 問題の診断 ===

* '''Htop''' should be your first port of call. The most obvious symptom will be a maxed-out CPU.
* Press F2, and under "Display options", enable "Detailed CPU time". Press F1 for an explanation of the colours used in the CPU bars. In particular, is the CPU spending most of its time responding to IRQs, or in Wait-IO (wio)?

=== サーバースレッド ===

'''Symptoms:''' Nothing seems to be very heavily loaded, but some operations on the client take a long time to complete for no apparent reason.

If your workload involves lots of small reads and writes (or if there are a lot of clients), there may not be enough threads running on the server to handle the quantity of queries. To check if this is the case, run the following command on one or more of the clients:

{{hc|# nfsstat -rc|
Client rpc stats:
calls retrans authrefrsh
113482 0 113484
}}

If the {{ic|retrans}} column contains a number larger than 0, the server is failing to respond to some NFS requests, and the number of threads should be increased.

To increase the number of threads on the server, edit the file {{ic|/etc/conf.d/nfs-server.conf}} and set the value in the {{ic|NFSD_OPTS}} variable.
For example, to set the number of threads to 32:
{{hc|/etc/conf.d/nfs-server.conf|
NFSD_OPTS="32"
}}

The default number of threads is 8. Try doubling this number until {{ic|retrans}} remains consistently at zero. Don't be afraid of increasing the number quite substantially. 256 threads may be quite reasonable, depending on the workload. You will need to restart the NFS server daemon each time you modify the configuration file. Bear in mind that the client statistics will only be reset to zero when the client is rebooted.

Use '''htop''' (disable the hiding of kernel threads) to keep an eye on how much work each nfsd thread is doing. If you reach a point where the {{ic|retrans}} values are non-zero, but you can see {{ic|nfsd}} threads on the server doing no work, something different is now causing your bottleneck, and you'll need to re-diagnose this new problem.

=== Close-to-open/flush-on-close ===

'''Symptoms:''' Your clients are writing many small files. The server CPU is not maxed out, but there is very high wait-IO, and the server disk seems to be churning more than you might expect.

In order to ensure data consistency across clients, the NFS protocol requires that the client's cache is flushed (all data is pushed to the server) whenever a file is closed after writing. Because the server is not allowed to buffer disk writes (if it crashes, the client won't realise the data wasn't written properly), the data is written to disk immediately before the client's request is completed. When you're writing lots of small files from the client, this means that the server spends most of its time waiting for small files to be written to its disk, which can cause a significant reduction in throughput.

See [http://docstore.mik.ua/orelly/networking_2ndEd/nfs/ch07_04.htm this excellent article] or the '''nfs''' manpage for more details on the close-to-open policy. There are several approaches to solving this problem:

==== nocto マウントオプション ====

{{Note|The linux kernel does not seem to honour this option properly. Files are still flushed when they're closed.}}

Does your situation match these conditions?

* The export you have mounted on the client is only going to be used by the one client.
* It doesn't matter too much if a file written on one client doesn't immediately appear on other clients.
* It doesn't matter if after a client has written a file, and the client thinks the file has been saved, and then the client crashes, the file may be lost.

If you're happy with the above conditions, you can use the '''nocto''' mount option, which will disable the close-to-open behaviour. See the '''nfs''' manpage for details.

==== async エクスポートオプション ====

Does your situation match these conditions?

* It's important that when a file is closed after writing on one client, it is:
** Immediately visible on all the other clients.
** Safely stored on the server, even if the client crashes immediately after closing the file.
* It's not important to you that if the server crashes:
** You may loose the files that were most recently written by clients.
** When the server is restarted, the clients will believe their recent files exist, even though they were actually lost.

In this situation, you can use {{ic|async}} instead of {{ic|sync}} in the server's {{ic|/etc/exports}} file for those specific exports. See the '''exports''' manual page for details. In this case, it does not make sense to use the {{ic|nocto}} mount option on the client.

=== バッファキャッシュサイズと MTU ===

'''Symptoms:''' High kernel or IRQ CPU usage, a very high packet count through the network card.

This is a trickier optimisation. Make sure this is definitely the problem before spending too much time on this. The default values are usually fine for most situations.

See [http://docstore.mik.ua/orelly/networking_2ndEd/nfs/ch07_03.htm this excellent article] for information about I/O buffering in NFS. Essentially, data is accumulated into buffers before being sent. The size of the buffer will affect the way data is transmitted over the network. The Maximum Transmission Unit (MTU) of the network equipment will also affect throughput, as the buffers need to be split into MTU-sized chunks before they're sent over the network. If your buffer size is too big, the kernel or hardware may spend too much time splitting it into MTU-sized chunks. If the buffer size is too small, there will be overhead involved in sending a very large number of small packets. You can use the '''rsize''' and '''wsize''' mount options on the client to alter the buffer cache size. To achieve the best throughput, you need to experiment and discover the best values for your setup.

It is possible to change the MTU of many network cards. If your clients are on a separate subnet (e.g. for a Beowulf cluster), it may be safe to configure all of the network cards to use a high MTU. This should be done in very-high-bandwidth environments.

See also the '''nfs''' manual page for more about '''rsize''' and '''wsize'''.

== デバッグ ==

=== rpcdebug を使う ===

Using {{ic|rpcdebug}} is the easiest way to manipulate the kernel interfaces in place of echoing bitmasks to /proc.

{| class="wikitable"
|-
! Option !! Description
|-
| -c || Clear the given debug flags
|-
| -s || Set the given debug flags
|-
| -m ''module'' || Specify which module's flags to set or clear.
|-
| -v || Increase the verbosity of rpcdebug's output
|-
| -h || Print a help message and exit. When combined with the -v option, also prints the available debug flags.
|}

For the '''-m''' option, the available modules are:

{| class="wikitable"
|-
! Module !! Description
|-
| nfsd || The NFS server
|-
| nfs || The NFS client
|-
| nlm || The Network Lock Manager, in either an NFS client or server
|-
| rpc || The Remote Procedure Call module, in either an NFS client or server
|}

Examples:
{{bc|
rpcdebug -m rpc -s all # sets all debug flags for RPC
rpcdebug -m rpc -c all # clears all debug flags for RPC

rpcdebug -m nfsd -s all # sets all debug flags for NFS Server
rpcdebug -m nfsd -c all # clears all debug flags for NFS Server
}}

Once the flags are set you can tail the journal for the debug output, usually {{ic|journalctl -fl}} or similar.

=== カーネルインターフェイス ===

A bitmask of the debug flags can be echoed into the interface to enable output to syslog; 0 is the default:

{{bc|
/proc/sys/sunrpc/nfsd_debug
/proc/sys/sunrpc/nfs_debug
/proc/sys/sunrpc/nlm_debug
/proc/sys/sunrpc/rpc_debug
}}

Sysctl controls are registered for these interfaces, so they can be used instead of echo:

{{bc|1=
sysctl -w sunrpc.rpc_debug=1023
sysctl -w sunrpc.rpc_debug=0

sysctl -w sunrpc.nfsd_debug=1023
sysctl -w sunrpc.nfsd_debug=0
}}

At runtime the server holds information that can be examined:

{{bc|
grep . /proc/net/rpc/*/content
cat /proc/fs/nfs/exports
cat /proc/net/rpc/nfsd
ls -l /proc/fs/nfsd
}}

A rundown of {{ic|/proc/net/rpc/nfsd}} (the userspace tool {{ic|nfsstat}} pretty-prints this info):

{{bc|1=
* rc (reply cache): <hits> <misses> <nocache>
- hits: client it's retransmitting
- misses: a operation that requires caching
- nocache: a operation that no requires caching

* fh (filehandle): <stale> <total-lookups> <anonlookups> <dir-not-in-cache> <nodir-not-in-cache>
- stale: file handle errors
- total-lookups, anonlookups, dir-not-in-cache, nodir-not-in-cache
. always seem to be zeros

* io (input/output): <bytes-read> <bytes-written>
- bytes-read: bytes read directly from disk
- bytes-written: bytes written to disk

* th (threads): <threads> <fullcnt> <10%-20%> <20%-30%> ... <90%-100%> <100%>
- threads: number of nfsd threads
- fullcnt: number of times that the last 10% of threads are busy
- 10%-20%, 20%-30% ... 90%-100%: 10 numbers representing 10-20%, 20-30% to 100%
. Counts the number of times a given interval are busy

* ra (read-ahead): <cache-size> <10%> <20%> ... <100%> <not-found>
- cache-size: always the double of number threads
- 10%, 20% ... 100%: how deep it found what was looking for
- not-found: not found in the read-ahead cache

* net: <netcnt> <netudpcnt> <nettcpcnt> <nettcpconn>
- netcnt: counts every read
- netudpcnt: counts every UDP packet it receives
- nettcpcnt: counts every time it receives data from a TCP connection
- nettcpconn: count every TCP connection it receives

* rpc: <rpccnt> <rpcbadfmt+rpcbadauth+rpcbadclnt> <rpcbadfmt> <rpcbadauth> <rpcbadclnt>
- rpccnt: counts all rpc operations
- rpcbadfmt: counts if while processing a RPC it encounters the following errors:
. err_bad_dir, err_bad_rpc, err_bad_prog, err_bad_vers, err_bad_proc, err_bad
- rpcbadauth: bad authentication
. does not count if you try to mount from a machine that it's not in your exports file
- rpcbadclnt: unused

* procN (N = vers): <vs_nproc> <null> <getattr> <setattr> <lookup> <access> <readlink> <read> <write> <create> <mkdir> <symlink> <mknod> <remove> <rmdir> <rename> <link> <readdir> <readdirplus> <fsstat> <fsinfo> <pathconf> <commit>
- vs_nproc: number of procedures for NFS version
. v2: nfsproc.c, 18
. v3: nfs3proc.c, 22
- v4, nfs4proc.c, 2
- statistics: generated from NFS operations at runtime

* proc4ops: <ops> <x..y>
- ops: the definition of LAST_NFS4_OP, OP_RELEASE_LOCKOWNER = 39, plus 1 (so 40); defined in nfs4.h
- x..y: the array of nfs_opcount up to LAST_NFS4_OP (nfsdstats.nfs4_opcount[i])
}}

=== NFSD デバッグフラグ ===
{{hc|/usr/include/linux/nfsd/debug.h|2=
/*
* knfsd debug flags
*/
#define NFSDDBG_SOCK 0x0001
#define NFSDDBG_FH 0x0002
#define NFSDDBG_EXPORT 0x0004
#define NFSDDBG_SVC 0x0008
#define NFSDDBG_PROC 0x0010
#define NFSDDBG_FILEOP 0x0020
#define NFSDDBG_AUTH 0x0040
#define NFSDDBG_REPCACHE 0x0080
#define NFSDDBG_XDR 0x0100
#define NFSDDBG_LOCKD 0x0200
#define NFSDDBG_ALL 0x7FFF
#define NFSDDBG_NOCHANGE 0xFFFF
}}

=== NFS デバッグフラグ ===
{{hc|/usr/include/linux/nfs_fs.h|2=
/*
* NFS debug flags
*/
#define NFSDBG_VFS 0x0001
#define NFSDBG_DIRCACHE 0x0002
#define NFSDBG_LOOKUPCACHE 0x0004
#define NFSDBG_PAGECACHE 0x0008
#define NFSDBG_PROC 0x0010
#define NFSDBG_XDR 0x0020
#define NFSDBG_FILE 0x0040
#define NFSDBG_ROOT 0x0080
#define NFSDBG_CALLBACK 0x0100
#define NFSDBG_CLIENT 0x0200
#define NFSDBG_MOUNT 0x0400
#define NFSDBG_FSCACHE 0x0800
#define NFSDBG_PNFS 0x1000
#define NFSDBG_PNFS_LD 0x2000
#define NFSDBG_STATE 0x4000
#define NFSDBG_ALL 0xFFFF
}}

=== NLM デバッグフラグ ===
{{hc|/usr/include/linux/lockd/debug.h|2=
/*
* Debug flags
*/
#define NLMDBG_SVC 0x0001
#define NLMDBG_CLIENT 0x0002
#define NLMDBG_CLNTLOCK 0x0004
#define NLMDBG_SVCLOCK 0x0008
#define NLMDBG_MONITOR 0x0010
#define NLMDBG_CLNTSUBS 0x0020
#define NLMDBG_SVCSUBS 0x0040
#define NLMDBG_HOSTCACHE 0x0080
#define NLMDBG_XDR 0x0100
#define NLMDBG_ALL 0x7fff
}}

=== RPC デバッグフラグ ===
{{hc|/usr/include/linux/sunrpc/debug.h|2=
/*
* RPC debug facilities
*/
#define RPCDBG_XPRT 0x0001
#define RPCDBG_CALL 0x0002
#define RPCDBG_DEBUG 0x0004
#define RPCDBG_NFS 0x0008
#define RPCDBG_AUTH 0x0010
#define RPCDBG_BIND 0x0020
#define RPCDBG_SCHED 0x0040
#define RPCDBG_TRANS 0x0080
#define RPCDBG_SVCXPRT 0x0100
#define RPCDBG_SVCDSP 0x0200
#define RPCDBG_MISC 0x0400
#define RPCDBG_CACHE 0x0800
#define RPCDBG_ALL 0x7fff
}}

=== 一般注記事項 ===
* While the number of threads can be increased at runtime via an echo to {{ic|/proc/fs/nfsd/threads}}, the cache size (double the threads, see the '''ra''' line of /proc/net/rpc/nfsd) is not dynamic. The NFS daemon must be restarted with the new thread size during initialization in order for the thread cache to properly adjust.

=== 参照 ===
* [https://github.com/torvalds/linux/tree/master/include/linux https://github.com/torvalds/linux/tree/master/include/linux]
* [http://linux.die.net/man/8/rpcdebug http://linux.die.net/man/8/rpcdebug]
* [http://utcc.utoronto.ca/~cks/space/blog/linux/NFSClientDebuggingBits http://utcc.utoronto.ca/~cks/space/blog/linux/NFSClientDebuggingBits]
* [http://www.novell.com/support/kb/doc.php?id=7011571 http://www.novell.com/support/kb/doc.php?id=7011571]
* [http://stromberg.dnsalias.org/~strombrg/NFS-troubleshooting-2.html http://stromberg.dnsalias.org/~strombrg/NFS-troubleshooting-2.html]
* [http://www.opensubscriber.com/message/nfs@lists.sourceforge.net/7833588.html http://www.opensubscriber.com/message/nfs@lists.sourceforge.net/7833588.html]

== 他の問題 ==

=== パーミッションの問題 ===

If you find that you cannot set the permissions on files properly, make sure the user/group you are chowning are on both the client and server.

If all your files are owned by {{ic|nobody}}, and you are using NFSv4, on both the client and server, you should:
* For systemd, ensure that the {{ic|nfs-idmapd}} service has been started.
* For initscripts, ensure that {{ic|NEED_IDMAPD}} is set to {{ic|YES}} in {{ic|/etc/conf.d/nfs-common.conf}}.

On some systems detecting the domain from FQDN minus hostname does not seem to work reliably. If files are still showing as {{ic|nobody}} after the above changes, edit /etc/idmapd.conf, ensure that {{ic|Domain}} is set to {{ic|FQDN minus hostname}}. For example:

{{hc|/etc/idmapd.conf|2=
[General]

Verbosity = 7
Pipefs-Directory = /var/lib/nfs/rpc_pipefs
Domain = yourdomain.local

[Mapping]

Nobody-User = nobody
Nobody-Group = nobody

[Translation]

Method = nsswitch
}}

If nfs-idmapd.service refuses to start because it cannot open the Pipefs-directory (defined in /etc/idmapd.conf and appended with '/nfs'), issue a mkdir-command and restart the daemon.

詳しくは [[NFS#ID マッピング]] を参照してください。