Re: [HTCondor-users] condor_drain error

[Curtis Spencer <curtis.spencer@xxxxxxxxxxxx>]

I ran that command and tried running `condor_drain`Â using the entire value of MyAddress but it hung and I had to exit. I also tried with the Ip address and machine alias but got the same errors as before.

```

$ condor_status -af:h Name Machine MyAddress
Name         Machine    ÂMyAddress                                           Â
slot1@condor-execute condor-execute <192.168.9.161:9618?addrs=192.168.9.161-9618&alias=condor-execute&noUDP&sock=startd_11727_5337>

$ sudo condor_drain -debug 192.168.9.161:9618?addrs=192.168.9.161-9618&alias=condor-execute&noUDP&sock=startd_11727_5337
[1] 41511
[2] 41512
[3] 41513
debian@condor-master:~$ -bash: noUDP: command not found
04/18/25 17:39:47 condor_read(): Socket closed abnormally when trying to read 5 bytes from startd 192.168.9.161:9618?addrs=192.168.9.161-9618, errno=104 Connection reset by peer
04/18/25 17:39:47 SECMAN: no classad from server, failing
04/18/25 17:39:47 ERROR: SECMAN:2011:Connection closed during command authorization. Probably due to an unknown command.
Attempt to send DRAIN_JOBS to startd <192.168.9.161:9618> failed
Failed to start DRAIN_JOBS command to 192.168.9.161:9618?addrs=192.168.9.161-9618
^C
[1] Â Exit 1 Â Â Â Â Â Â Â Â Âsudo condor_drain -debug 192.168.9.161:9618?addrs=192.168.9.161-9618
[2]- ÂDone          Âalias=condor-execute
[3]+ ÂExit 127 Â Â Â Â Â Â Â ÂnoUDP

$ sudo condor_drain -debug 192.168.9.161
04/18/25 17:38:45 Can't find address for startd 192.168.9.161
ERROR: Can't find address for startd 192.168.9.161

$ sudo condor_drain -debug condor-execute
ERROR: unknown host condor-execute

```

Thanks,

Curtis

On Fri, Apr 18, 2025 at 7:17âAM John M Knoeller <johnkn@xxxxxxxxxxx> wrote:

The HTCondor tools mostly don't use DNS to locate daemons when they want to send commands.Â

The way most HTCondor tools, including condor_drain, determine the address of a daemon is by querying the collector, so the argument you pass must be the name of the daemon in the collector.Â

Try runningÂ

condor_status -af:h Name Machine MyAddress

The MyAddress value is what condor_drain needs to lookup in order to see send the drain command, ÂIt will look for entries in the collector where either the Name or the Machine value matches what you passed to condor_drain. ÂÂ

-tj

---

From: HTCondor-users <htcondor-users-bounces@xxxxxxxxxxx> on behalf of Curtis Spencer via HTCondor-users <htcondor-users@xxxxxxxxxxx>
Sent: Thursday, April 17, 2025 3:43 PM
To: HTCondor-Users Mail List <htcondor-users@xxxxxxxxxxx>
Cc: Curtis Spencer <curtis.spencer@xxxxxxxxxxxx>
Subject: [HTCondor-users] condor_drain error

Â

I have a test condor pool with two nodes (installed using `get_htcondor`):

* Node A (hostname `condor-master`; IP 192.168.9.7) has `use role:get_htcondor_central_manager` and `use role:get_htcondor_submit` roles

* Node B (hostname `condor-execute`; IP 192.168.9.161) has `use role:get_htcondor_execute`

I ran `systemctl status condor` onÂboth nodes to confirm that the master has condor_collector, condor_negotiator, and condor_schedd running and that the execute nodeÂhas condor_startd running.

Both nodes have `use security:recommended` in `/etc/condor/config.d/00-security`.

I have run `condor_status` and confirmed that the execute machine has joined the poolÂand I have run `condor_submit` with a test script and confirmed that the job ran.

I have copied the `/etc/condor/passwords.d/POOL` file from the master node to the execute node and confirmed 0600 permissions for that file on both nodes.

I have runÂ`condor_token_request` on the master node and approved the request on the execute node using `condor_token_request_approve` and stored the returned key in `/etc/condor/tokens.d/admin@condor` on the master node.

I then ran `condor_drain -debug 192.168.9.161` but gotÂthis error: "Can't find address for startd 192.168.9.161". I thought this could be related to using the IP address instead of a DNS name so I added an entry to my /etc/hosts file and ran `condor_drain -debu condor-execute` but I got this error: "ERROR: unknown host condor-execute"

Conceptually, I feel like I understand how IDTOKEN auth is supposed to work (and to some extent, I think it is working since the execute machine was able to join the pool), but I can't figure out why `condor_drain` won't work.

Thanks,

Curtis