File list and descriptions:
 
My first aplication was page67.c, helped with de Ing. Luis Haquin
(really, I know the informix structure, they know C!) Togheter we make
these first routine.
 
Informix track the chunks status in the reserved pages 6 and 7, using
alternatively one and other.  If a hard drive fail (or by mistake a
permision is changed), one or more chunks are marked DOWN.
 
These utility must be used with the engine OFF-LINE, because the values
of these page are in memory and update with these values when the engine
shut down.
 
The page67.c take two or four parameters
 
        page67 rootpath page_number [chunk_number 0|1 ]
 
where
 
    rootpath is where to find the first chunk (like ROOTPATH in tbconfig)
 
    page_number MUST BE 6 or 7
 
With these two parameters, the utility show information stored in the
indicated page,
 
i.e
 
informix> page67 /dev/RIFX1 6
Page numero: 6
chk offset   size     free     dbs flags pathname
1   0        500000   3599     1   40    /dev/RIFX1
2   0        75000    295      1   40    /dev/RIFX2
3   80000    400000   355      1   40    /dev/RIFX3
4   0        500000   846      1   40    /dev/RIFX4
5   0        500000   891      1   40    /dev/RIFX5
6   0        1000000  5213     1   40    /dev/RIFX6
7   0        1000000  260648   1   40    /dev/RIFX7
   
If one chunk is down, the flag is 20, not 40.
 
With four parameters, you can make one chunk down or up especifing the
chunk number and the new status (0=down, 1=up)
 
informix> page67 /dev/RIFXIG1 6 7 0
 
These command put de chunk 7 (/dev/RIFXIG7) down in the page 6, repeate
the command for page 7 (page67 /dev/RIFXIG1 7 7 0)
 
If you run again the page67 /dev/RIFX1 6, the flag for the chunk number 7
is 20.
 
If you have some chunk down, you can put them UP using the utility with
the last parameter set to 1.
 
Sorry for my english, I hope the explanation be understandable.
 
 
The other utility named rchunk.c take advantage of one definition of my
instalations, all the instances takes a unique indentifier of four
digits, then, the chunks are named using one rule like /dev/RIFXnnnna,
/dev/RIFXnnnnb, /dev/RIFXnnnnc, etc.
 
Sometimes, I need to have two copies of the same instance in the same
machine, boths online, but the name of the chunks make this impossible.
 
I develope a utility with change the four digits of the chunk number in
the reserved pages of the roodbs.
 
Example:
 
I have one instance with the next chunks:
 
/dev/RIFX0001a, /dev/RIFX0001b, /dev/RIFX0001c.
 
 
To duplicate the instance, follow these steps
 
a) make a archive
b) make a copy of the tbconfig (tbconfig.copy)
c) shut down the engine
d) run the rchunk utility: rchunk /dev/RIFX0001a 0002
 
The name of the chunks in the reserved page is changed from
/dev/RIFX0001a, /dev/RIFX0001b, /dev/RIFX0001c to /dev/RIFX0002a,
/dev/RIFX0002b, /dev/RIFX0002c.
 
e) change the value of ROOTPATH in the tbconfig.copy from /dev/RIFX0001a
to /dev/RIFX0002a
f) change the SERVERNUM in the tbconfig.new
g) change the names of the devices in the Operation System
h) set TBCONFIG=tbconfig.copy
i)  put the engine online (some messages appears in the log file showing
the change of the ROOTPATH).
j) create the devices /dev/RIFX0001a, /dev/RIFX0001b, /dev/RIFX0001c.
k) set TBCONFIG=tbconfig
l) restore de backup
m) done!
 
The tbconfig.copy points to the copy data, and tbconfig point to original
data.
 
 
These utilities are devolped under SCO Unix 5.0.4 (development option),
and tested on online 5.10.uc1 with cooked file and raw devices
 
compile instruction:
 
cc -o page67 page67.c
 
 
the rchunk.c use the definitions of informix.h and the library base.c
(separated for common use)
 
cc -o rchunk rchunk base
 
For any comment or suggestion, please e-mail me at
gtobares@redmegatone.com