12/04/98HEPNT - Windows NT Days1 NT Cluster & MS Dfs Gunter Trowitzsch & DESY WindowsNT Group

DESY 12/04/98HEPNT - Windows NT Days2 Server Configuration l Unique OS software configuration for all servers: n WNT 4.0 and Service Pack 3 l Modular hardware configurations for most of all servers n DEC Prioris base system : 200 MHz Pentium Pro : 128 MB memory n External SCSI disk systems 2 mirrored hot swappable system disks n Fast Ethernet è PDC, Dfs Server, Mail Server, Cluster Nodes, BDC Zeuthen l BDC Hamburg : PC, 133 MHz Pentium II, 64 MB memory l WINS HH & ZN : PC, 90 MHz Pentium, 32 MB memory l Fileserver Zeuthen : Alpha, 266 MHz, 128 MB memory

DESY 12/04/98HEPNT - Windows NT Days3 Print Server l Inside DESYNT the print jobs are spooled over the NT print server to the central UNIX print server. l At the moment the print server is a PC with a 166 MHz Pentium and 128 MB memory. ásome smaller problems - availability and scaling l Test of Microsoft Cluster n successful n fail-over works timing problems: server failure  starting a print job  To improve the situation we will upgrade to Microsoft Cluster with two nodes.  still a weak point - no job control over the whole process

DESY 12/04/98HEPNT - Windows NT Days4 Home Directory Cluster l Digital WNT cluster l DEC Prioris MX6200, 200 MHz Pentium Pro l 256 MB memory l 2 shared differential SCSI buses l 2 DEC RA310 RAID array with 2 RAID 5 sets l 110 GByte disk space MX MB MX MB RA310

DESY 12/04/98HEPNT - Windows NT Days5 NetInstall Application Cluster l Digital WNT Cluster l Digital Server 3000, 266 MHz Pentium II, l 128 MB memory, l 1 shared differential SCSI bus l DEC RA310 RAID array l 1 RAID 5 set l 25 GByte disk space DS MB DS MB RA310

DESY 12/04/98HEPNT - Windows NT Days6 DESYNT The DESY WindowsNT Infrastructure BDC WINS File Server DESY Zeuthen LAN 4 MBIT Leased Line Data Replication PDC DFS SQLSMS BDC WINS DESY Hamburg LAN Print NI RAID Set HD RAID Set

DESY 12/04/98HEPNT - Windows NT Days7 MS Dfs at DESY l MS Dfs is a redirector for UNC requests single tree structure for multiple shared volumes located on different servers redirection of client connections to shares via redirection table on the Dfs server MS Dfs l Hardware n standard DESY server configuration n DEC Prioris, 200MHz Pentium Pro, 128 MB memory, Fast Ethernet n NT4 Server, SP3 l Performance n Server : CPU consumption less then 5 % : 40 MB memory ( ~ 3000 entries ) n Client: : first connection takes some time 0.5 to 2 seconds : Dfs cache is updated regular (not for active connections) : no performance losses (compared to a “direct” connection)

DESY 12/04/98HEPNT - Windows NT Days8 Dfs Administration

DESY 12/04/98HEPNT - Windows NT Days9 Maintenance l simple l daily backup of the configuration table n using the scheduler service n private dump utility dfscmd /view … > …./full separates with blanks !!  useless restore by the help of dfsadmin (~30 minutes) l Replication of the configuration table between Hamburg and Zeuthen

DESY 12/04/98HEPNT - Windows NT Days10 Experiences l very useful service l used to provide (read) access to all home directories l not used to connect the user home directory (direct share connection) l used to provide access to the NetInstall applications or other shared offered applications and disk space l simple fail-over by using the alternative path n replication of file space - unique file/directory structures on servers n partial used between Hamburg and Zeuthen (NetInstall packages) l ACL handling is difficult up to NT4 with SP3 n no GUI to handle the ACL’s only the command line tools cacls and xcacls are available n full integration in to the Explorer with SP4

DESY 12/04/98HEPNT - Windows NT Days11 Dfs Summary l Advantages n it´s not a gateway, just a small redirector n no performance losses n easy to configure and to maintain n small load for client and server l Disadvantages n it´s a redirector, not a gateway : one can not reconfigure the client : client decides when the internal cache has to be updated n no nested links/redirections n ACL handling not integrated as desired n single point of failure - up to now not integrated in cluster solutions

DESY 12/04/98HEPNT - Windows NT Days12 What is MS Dfs l Redirector for UNC requests dfsadmin is the Management GUI n entries like: if user references this path redirect him to... l Redirection implemented on the client (NT4.0, W95AddON, W98) l “logical” drive/directory structure l an alternative path my be configured (for fail-over)