omshell reservation

Gregory Sloop gregs at
Mon Jul 20 14:37:34 UTC 2020

Ohhhh... Very cool bash script, BTW.
(my bash-foo is weak! Grasshopper will remember this tidbit!)

I owe you a beer, or something!
Thanks a bunch!

[BTW, where/how do you determine what flag values to use - other than asking a dev? Is it documented somewhere other than just source code?]

Again, thanks so much!


Set flags value to 4:

A bit of bash:

omshell 1>$errfile 2>&1 << END_OF_INPUT
server localhost
port 7911
new lease
set ip-address = $addr
set flags = 4

You should see the word "reserved" added to the lease:

lease {
  starts 1 2020/07/20 14:00:00;
  ends 1 2020/07/20 15:00:00;
  tstp 1 2020/07/20 15:00:00;
  cltt 1 2020/07/20 14:00:00;
  binding state free;
  hardware ethernet 08:00:27:25:d3:f4;
  set remote-handle = %1;

On 7/20/20 9:18 AM, Gregory Sloop wrote:

Re: omshell reservation
Still struggling with this.

Perhaps I wasn't clear, but question #3 was about what I see in the leases file.

After the lease is expired, here's what I find in the leases file.
lease {
  starts 5 2020/07/17 22:42:54;
  ends 5 2020/07/17 22:42:52;
  tstp 5 2020/07/17 22:42:54;
  tsfp 5 2020/07/17 22:42:54;
  atsfp 5 2020/07/17 22:42:54;
  cltt 5 2020/07/17 18:42:52;
  binding state backup;
  hardware ethernet 98:01:a7:ff:ff:ff;
  uid "\000\000\000\000\000\000";
  set remote-handle = %3;
  set vendor-class-identifier = "MSFT 5.0";


The only thing that I noticed that changed after setting flags was the
  set remote-handle = %3;
And I can't find any detail about what "remote-handle" is.
Does it even apply to reservations?


gsuca> Great sleuthing there Greg. omshell typically writes something into the
gsuca> leases file, so have a look for the *last* record for the given IP
gsuca> address and see what is in it, especially compared to earlier ones.

gsuca> regards,
gsuca> -glenn

gsuca> On 2020-07-18 08:02, Gregory Sloop wrote:
>> I'm trying to accomplish a "reservation" using omshell.

>> But just like Unicorns, Santa, and the Easter Bunny, I'm not sure it
>> really exists!
>> Ok, ok. Yeah, it probably does - but I can't find an example anywhere
>> that's confirmed to work.

>> This quote from long ago summarizes my feelings so far. [probably
>> nearly everyone's, actually]

>>> involves a rather fragile and often misbehaving omshell
>>> process where the only "documentation" is half a mailing list thread
>>> from ten years ago

>> So, from what I've gleaned, this is what I'm doing.
>> After you get into omshell
>> ---
>> port xxx
>> server localhost
>> key...
>> set ip-sddress=
>> open
>> ---

>> I get a listing of the lease for
>> Then it looks like I should use
>> set flag = 8
>> update
>> [And surprisingly the update takes. It feels like magic when you
>> finally hit on the right incantation!]

>> So, my questions
>> 1) Is setting flags = 8 the right thing to set for a reserved lease?
>> (I'm guessing from that even less than half a thread from 10y ago.)

>> 2) How can I tell if it actually took?

>> 3) And perhaps realated to #2 - what's this mean in the lease: set
>> remote-handle = %3; (I see that after setting flag = 8

>> TIA
>> -Greg
>> _______________________________________________
>> ISC funds the development of this software with paid support
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>> information.

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Gregory Sloop, Principal: Sloop Network & Computer Consulting
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