docs/docbook/projdoc/Portability.sgml

   1 <chapter id="Portability">
   2 <chapterinfo>
   3         &author.jelmer;
   4 </chapterinfo>
   5
   6 <title>Portability</title>
   7
   8 <para>Samba works on a wide range of platforms but the interface all the
   9 platforms provide is not always compatible. This chapter contains
  10 platform-specific information about compiling and using samba.</para>
  11
  12 <sect1>
  13 <title>HPUX</title>
  14
  15 <para>
  16 HP's implementation of supplementary groups is, er, non-standard (for
  17 hysterical reasons).  There are two group files, /etc/group and
  18 /etc/logingroup; the system maps UIDs to numbers using the former, but
  19 initgroups() reads the latter.  Most system admins who know the ropes
  20 symlink /etc/group to /etc/logingroup (hard link doesn't work for reasons
  21 too stupid to go into here).  initgroups() will complain if one of the
  22 groups you're in in /etc/logingroup has what it considers to be an invalid
  23 ID, which means outside the range [0..UID_MAX], where UID_MAX is (I think)
  24 60000 currently on HP-UX.  This precludes -2 and 65534, the usual 'nobody'
  25 GIDs.
  26 </para>
  27
  28 <para>
  29 If you encounter this problem, make sure that the programs that are failing
  30 to initgroups() be run as users not in any groups with GIDs outside the
  31 allowed range.
  32 </para>
  33
  34 <para>This is documented in the HP manual pages under setgroups(2) and passwd(4).
  35 </para>
  36
  37 <para>
  38 On HPUX you must use gcc or the HP Ansi compiler. The free compiler
  39 that comes with HP-UX is not Ansi compliant and cannot compile
  40 Samba.
  41 </para>
  42
  43 </sect1>
  44
  45 <sect1>
  46 <title>SCO Unix</title>
  47
  48 <para>
  49 If you run an old version of  SCO Unix then you may need to get important
  50 TCP/IP patches for Samba to work correctly. Without the patch, you may
  51 encounter corrupt data transfers using samba.
  52 </para>
  53
  54 <para>
  55 The patch you need is UOD385 Connection Drivers SLS. It is available from
  56 SCO (ftp.sco.com, directory SLS, files uod385a.Z and uod385a.ltr.Z).
  57 </para>
  58
  59 </sect1>
  60
  61 <sect1>
  62 <title>DNIX</title>
  63
  64 <para>
  65 DNIX has a problem with seteuid() and setegid(). These routines are
  66 needed for Samba to work correctly, but they were left out of the DNIX
  67 C library for some reason.
  68 </para>
  69
  70 <para>
  71 For this reason Samba by default defines the macro NO_EID in the DNIX
  72 section of includes.h. This works around the problem in a limited way,
  73 but it is far from ideal, some things still won't work right.
  74 </para>
  75
  76 <para>
  77 To fix the problem properly you need to assemble the following two
  78 functions and then either add them to your C library or link them into
  79 Samba.
  80 </para>
  81
  82 <para>
  83 put this in the file <filename>setegid.s</filename>:
  84 </para>
  85
  86 <para><programlisting>
  87         .globl  _setegid
  88 _setegid:
  89         moveq   #47,d0
  90         movl    #100,a0
  91         moveq   #1,d1
  92         movl    4(sp),a1
  93         trap    #9
  94         bccs    1$
  95         jmp     cerror
  96 1$:
  97         clrl    d0
  98         rts
  99 </programlisting></para>
 100
 101 <para>
 102 put this in the file <filename>seteuid.s</filename>:
 103 </para>
 104
 105 <para><programlisting>
 106         .globl  _seteuid
 107 _seteuid:
 108         moveq   #47,d0
 109         movl    #100,a0
 110         moveq   #0,d1
 111         movl    4(sp),a1
 112         trap    #9
 113         bccs    1$
 114         jmp     cerror
 115 1$:
 116         clrl    d0
 117         rts
 118 </programlisting></para>
 119
 120 <para>
 121 after creating the above files you then assemble them using
 122 </para>
 123
 124 <para><command>as seteuid.s</command></para>
 125 <para><command>as setegid.s</command></para>
 126
 127 <para>
 128 that should produce the files <filename>seteuid.o</filename> and
 129 <filename>setegid.o</filename>
 130 </para>
 131
 132 <para>
 133 then you need to add these to the LIBSM line in the DNIX section of
 134 the Samba Makefile. Your LIBSM line will then look something like this:
 135 </para>
 136
 137 <para><programlisting>
 138 LIBSM = setegid.o seteuid.o -ln
 139 </programlisting></para>
 140
 141 <para>
 142 You should then remove the line:
 143 </para>
 144
 145 <para><programlisting>
 146 #define NO_EID
 147 </programlisting></para>
 148
 149 <para>from the DNIX section of <filename>includes.h</filename></para>
 150
 151 </sect1>
 152
 153 <sect1>
 154 <title>RedHat Linux Rembrandt-II</title>
 155
 156 <para>
 157 By default RedHat Rembrandt-II during installation adds an
 158 entry to /etc/hosts as follows:
 159 <programlisting>
 160         127.0.0.1 loopback "hostname"."domainname"
 161 </programlisting>
 162 </para>
 163
 164 <para>
 165 This causes Samba to loop back onto the loopback interface.
 166 The result is that Samba fails to communicate correctly with
 167 the world and therefor may fail to correctly negotiate who
 168 is the master browse list holder and who is the master browser.
 169 </para>
 170
 171 <para>
 172 Corrective Action:      Delete the entry after the word loopback
 173         in the line starting 127.0.0.1
 174 </para>
 175 </sect1>
 176
 177 <sect1>
 178 <title>AIX</title>
 179 <sect2>
 180 <title>Sequential Read Ahead</title>
 181 <!-- From an email by William Jojo <jojowil@hvcc.edu> -->
 182 <para>
 183 Disabling Sequential Read Ahead using <userinput>vmtune -r 0</userinput> improves
 184 samba performance significally.
 185 </para>
 186 </sect2>
 187 </sect1>
 188
 189 <sect1>
 190 <title>Solaris</title>
 191
 192 <sect2>
 193 <title>Locking improvements</title>
 194
 195 <para>Some people have been experiencing problems with F_SETLKW64/fcntl
 196 when running samba on solaris. The built in file locking mechanism was
 197 not scalable. Performance would degrade to the point where processes would
 198 get into loops of trying to lock a file. It woul try a lock, then fail,
 199 then try again. The lock attempt was failing before the grant was
 200 occurring. So the visible manifestation of this would be a handful of
 201 processes stealing all of the CPU, and when they were trussed they would
 202 be stuck if F_SETLKW64 loops.
 203 </para>
 204
 205 <para>
 206 Sun released patches for Solaris 2.6, 8, and 9. The patch for Solaris 7
 207 has not been released yet.
 208 </para>
 209
 210 <para>
 211 The patch revision for 2.6 is 105181-34
 212 for 8 is 108528-19
 213 and for 9 is 112233-04
 214 </para>
 215
 216 <para>
 217 After the install of these patches it is recommended to reconfigure
 218 and rebuild samba.
 219 </para>
 220
 221 <para>Thanks to Joe Meslovich for reporting</para>
 222
 223 </sect2>
 224
 225 <sect2 id="winbind-solaris9">
 226 <title>Winbind on Solaris 9</title>
 227 <para>
 228 Nsswitch on Solaris 9 refuses to use the winbind nss module.  This behavior
 229 is fixed by Sun in patch 113476-05 which as of March 2003 is not in any
 230 roll-up packages.
 231 </para>
 232 </sect2>
 233 </sect1>
 234
 235 </chapter>