我要用Kerberos为NFSv4设置一个测试安装了。
机器从LDAP获取用户信息，从Kerberos获取凭据。我可以使用使用Kerberos的帐户登录到机器，也就是说，包括PAM在内的基本Kerberos设置正在运行。我可以使用基于主机的访问设置NFSv4，它也运行得很好。
因此，下一步我将子网掩码更改为'krb5'。
mount -t nfs4 -o sec=krb5 nfs4.mgr:/test mnt
mount.nfs4: access denied by server while mounting nfs4.mgr:/test
给gssd几个-v开关，我在日志中看到以下内容:
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: handling gssd upcall (/var/lib/nfs/rpc_pipefs/nfs/clntc)
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: handle_gssd_upcall: 'mech=krb5 uid=0 '
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: handling krb5 upcall (/var/lib/nfs/rpc_pipefs/nfs/clntc)
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: process_krb5_upcall: service is '<null>'
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: Full hostname for 'nfs4.mgr' is 'nfs4.mgr'
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: Full hostname for 'nfs4.mgr' is 'nfs4.mgr'
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: Key table entry not found while getting keytab entry for 'root/nfs4.mgr@MGR'
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: Success getting keytab entry for 'nfs/nfs4.mgr@MGR'
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: INFO: Credentials in CC 'FILE:/tmp/krb5cc_machine_MGR' are good until 1358369976
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: INFO: Credentials in CC 'FILE:/tmp/krb5cc_machine_MGR' are good until 1358369976
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: using FILE:/tmp/krb5cc_machine_MGR as credentials cache for machine creds
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: using environment variable to select krb5 ccache FILE:/tmp/krb5cc_machine_MGR
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: creating context using fsuid 0 (save_uid 0)
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: creating tcp client for server nfs4.mgr
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: DEBUG: port already set to 2049
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: creating context with server nfs@nfs4.mgr
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: in authgss_create_default()
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: in authgss_create()
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: authgss_create: name is 0x1bbee10
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: authgss_create: gd->name is 0x1bb46e0
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: in authgss_refresh()
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: struct rpc_gss_sec:
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: mechanism_OID: { 1 2 134 72 134 247 18 1 2 2 }
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: qop: 0
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: service: 1
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: cred: 0x1bb9ae0
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: req_flags: 00000002
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: rpcsec_gss: gss_init_sec_context: (major) Unspecified GSS failure. Minor code may provide more information - (minor) No supported encryption types (config file error?)
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: in authgss_destroy()
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: in authgss_destroy_context()
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: authgss_destroy: freeing name 0x1bb46e0
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: authgss_create_default: freeing name 0x1bbee10
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: WARNING: Failed to create krb5 context for user with uid 0 for server nfs4.mgr
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: WARNING: Failed to create machine krb5 context with credentials cache FILE:/tmp/krb5cc_machine_MGR for server nfs4.mgr
Jan 15 22:00:11 nfs4 rpc.gssd[8116]: WARNING: Machine cache is prematurely expired or corrupted trying to recreate cache for server nfs4.mgr
每次挂载调用都会发生两次。知道这是什么意思吗?它可能引用哪个配置文件?
谢谢你的帮助。
我相信NFSv4在Debian squeeze中的实现仍然是DES-only。(这在相当长一段时间内是NFSv4实现的一个问题。)但是，所有现代Kerberos实现在默认情况下都不再允许DES，因为它对于良好的安全实践来说太弱了。
至少，您可能需要添加:
allow_weak_crypto = true
到客户端/etc/krb5.conf的[libdefaults]区段。您的KDC还需要支持DES服务票证请求。您还需要确保NFSv4服务器使用的Kerberos主体仅具有DES enctypes;如果它有任何其他enctype，客户端会更喜欢它们(因为它们更强)，但是服务器将无法理解身份验证。