Re: Swapping IP address between CPU's

[bdietz@xxxxxx]

Here is a quick CLLE that clears the ARP cache on the 400 for a given line:

Source type CLLE

pgm      parm(&line)
/*  CRTBNDCL   PGM(your-lib/CLRARP)             +
               SRCFILE(your-lib/QCLSRC)         +
               SRCMBR(CLRARP)              */
 dcl &line *char 10
             CALLPRC    PRC('QtocRmvARPTblE') PARM(&LINE 0 '*ALL ' +
                          X'00000000')
   end:
       endpgm



-------------------------
 Bryan Dietz
3X Corporation
614-410-9205





midrange-l-bounces@xxxxxxxxxxxx wrote on 08/09/2003 04:27:04 AM:

> One addition:
>
> the AS/400 is quite strannge in behaviour concerning IP-caches:
> one thing I know for sure is that even V5R2 machines need to be IPLed (!)
> to clear their own ARP-caches. (to resolve other machines)
> Maybe there is a PTF to fix this, there should be at least a
"clear"-command
> for the ARP-table.
> When designing hot-swap scenarios you should know about this
> ill behaviour, because this fools every switch / router in your network.
> Been there, learned it the hard way ... during a long night.
>
> HTH, Philipp Rusch
>
>
> Philipp Rusch schrieb:
>
> > Rob,
> > this *should* be no issue, but you are talking of the ARP cache, where
> > mac addresses associated with their resp. IP-addresses.
> > This cache can be reset or manipulated through the ARP command,
> > Remote manipulation is possible through the means of the ARPING
> > command, which can add/modify entries of the ARP cache table.
> > I am not shure about the command line parameters, though.
> >
> > HTH, regards from Germany, Philipp Rusch
> >
> > rob@xxxxxxxxx schrieb:
> >
> > > As a poor man's hotsite during our scheduled downtimes we plan on
doing
> > > the following:
> > > ENDTCPIFC INTNETADR('xxx.xxx.xxx.xxx') on the primary iSeries
> > > Lock all libraries pertaining to one division.  Save them to a save
file.
> > > Send them over to our backup.  Verify they've arrived on the backup.
Drop
> > > the primary.
> > > Restore the libraries.  STRTCPIFC INTNETADR('xxx.xxx.xxx.xxx').  Let
the
> > > user's have their way.
> > >
> > > However I've been told that the DNS server in our network needs to
have
> > > it's cache reset to no longer associate that ip address with the old
mac
> > > address.  Currently that involves telnetting into the router, etc.  I
> > > thought about scripting some telnet session, much the same as you can
> > > script a ftp session.  Is that possible?
> > >
> > > Then it was suggested to me that I script a SNMP request.  Evidently
they
> > > can do more security on that.  And the thought of having router admin
> > > passwords buried in script files was not very appealing to them.  I
can
> > > respect that.  How would one do that from the iSeries?
> > >
> > > Rob Berendt
> > > --