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DAOS Command Fails with "Transport layer mercury error" on CentOS 7.9

northernlights from Bombay — Mon, 10 Jun 2024 21:06:00 GMT

Hello,

I'm encountering an issue when running the daos cont create command on my DAOS setup. The command fails with a "Transport layer mercury error." Below are the details of the error and my setup:

Command and Error Message:

[root@client2 ~]# daos cont create tank --label mycont
external ERR # [5323.920594] mercury->msg: [error] /builddir/build/BUILD/mercury-2.1.0rc4/src/na/na_ofi.c:3047
# na_ofi_msg_send(): fi_tsend() failed, rc: -2 (No such file or directory)
external ERR # [5323.921055] mercury->hg: [error] /builddir/build/BUILD/mercury-2.1.0rc4/src/mercury_core.c:2727
# hg_core_forward_na(): Could not post send for input buffer (NA_NOENTRY)
hg ERR src/cart/crt_hg.c:1104 crt_hg_req_send_cb(0x2a5c8c0) [opc=0x1020004 (DAOS) rpcid=0x18ea69b600000000 rank:tag=0 ] RPC failed; rc: DER_HG(-1020): 'Transport layer mercury error'
mgmt ERR src/mgmt/cli_mgmt.c:882 dc_mgmt_pool_find() tank: failed to get PS replicas from 1 servers, DER_HG(-1020): 'Transport layer mercury error'
pool ERR src/pool/cli.c:198 dc_pool_choose_svc_rank() 00000000:tank: dc_mgmt_pool_find() failed, DER_HG(-1020): 'Transport layer mercury error'
pool ERR src/pool/cli.c:503 dc_pool_connect_internal() 00000000:tank: cannot find pool service: DER_HG(-1020): 'Transport layer mercury error'
ERROR: daos: DER_HG(-1020): Transport layer mercury error

Environment Details:

DAOS Version: daos-2.0.3-5.el7.x86_64
DAOS Client Version: daos-client-2.0.3-5.el7.x86_64
Libfabric Version: libfabric-1.15.1-1.el7.x86_64
Mercury Version: mercury-2.1.0~rc4-9.el7.x86_64
CentOS Version: CentOS 7.9
Fabric Interface: enp0s3

Additional Information:

[root@server ~]# ip addr
1: lo: <loopback,up,lower_up> mtu 65536 qdisc noqueue state UNKNOWN group default qlen 1000
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
valid_lft forever preferred_lft forever
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
2: enp0s3: <broadcast,multicast,up,lower_up> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 08:00:27:bd:95:c2 brd ff:ff:ff:ff:ff:ff
inet 10.0.2.15/24 brd 10.0.2.255 scope global noprefixroute dynamic enp0s3
valid_lft 564sec preferred_lft 564sec
inet6 fe80::e25:a2fd:9904:a8ac/64 scope link noprefixroute
valid_lft forever preferred_lft forever
3: enp0s8: <broadcast,multicast,up,lower_up> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 08:00:27:bb:cb:4d brd ff:ff:ff:ff:ff:ff
inet 192.168.56.104/24 brd 192.168.56.255 scope global noprefixroute dynamic enp0s8
valid_lft 370sec preferred_lft 370sec
inet6 fe80::8d85:5b39:5f73:6e0b/64 scope link noprefixroute
valid_lft forever preferred_lft forever

I have also mentioned the DAOS server, client, and agent configuration files for reference.

DAOS Server
## default: daos_server
name: daos_server
#
#
## Access points
## Immutable after running "dmg storage format".
#
## To operate, DAOS will need a quorum of access point nodes to be available.
## Must have the same value for all agents and servers in a system.
## Hosts can be specified with or without port. The default port that is set
## up in port: will be used if a port is not specified here.
#
## default: hostname of this node
access_points: ['10.0.2.15']
#
#
## Default control plane port
#
## Port number to bind daos_server to. This will also be used when connecting
## to access points, unless a port is specified in access_points:
#
## default: 10001
port: 10001
#
#
## Transport credentials specifying certificates to secure communications
#
transport_config:
# # In order to disable transport security, uncomment and set allow_insecure
# # to true. Not recommended for production configurations.
allow_insecure: true
#
# # Location where daos_server will look for Client certificates
client_cert_dir: /etc/daos/certs/clients
# # Custom CA Root certificate for generated certs
ca_cert: /etc/daos/certs/daosCA.crt
# # Server certificate for use in TLS handshakes
cert: /etc/daos/certs/server.crt
# # Key portion of Server Certificate
key: /etc/daos/certs/server.key
provider: ofi+sockets
socket_dir: /var/run/daos_server
nr_hugepages: 4096
control_log_mask: DEBUG
control_log_file: /tmp/daos_server.log
helper_log_file: /tmp/daos_admin.log
engines:
-
targets: 8
nr_xs_helpers: 0
fabric_iface: enp0s3
fabric_iface_port: 31316
log_mask: INFO
log_file: /tmp/daos_engine_0.log
env_vars:
- CRT_TIMEOUT=30

scm_mount: /mnt/daos0
scm_class: ram
scm_size: 8

DAOS Control file

# default: daos_server
name: daos_server

# Default destination port to use when connecting to hosts in the hostlist.
# default: 10001
port: 10001

# Hostlist, a comma separated list of addresses (hostnames or IPv4 addresses).
# default: ['localhost']
hostlist: ['10.0.2.15']

## Transport Credentials Specifying certificates to secure communications

transport_config:
# # In order to disable transport security, uncomment and set allow_insecure
# # to true. Not recommended for production configurations.
allow_insecure: true
#
# # Custom CA Root certificate for generated certs
ca_cert: /etc/daos/certs/daosCA.crt
# # Admin certificate for use in TLS handshakes
cert: /etc/daos/certs/admin.crt
# # Key portion of Admin Certificate
key: /etc/daos/certs/admin.key

DAOS Agent file
# default: daos_server
name: daos_server

# Management server access points
# Must have the same value for all agents and servers in a system.
# default: hostname of this node
access_points: ['10.0.2.15']

# Force different port number to connect to access points.
# default: 10001
port: 10001

## Transport Credentials Specifying certificates to secure communications
#
transport_config:
# # In order to disable transport security, uncomment and set allow_insecure
# # to true. Not recommended for production configurations.
allow_insecure: true
#
# # Custom CA Root certificate for generated certs
ca_cert: /etc/daos/certs/daosCA.crt
# # Agent certificate for use in TLS handshakes
cert: /etc/daos/certs/agent.crt
# # Key portion of Agent Certificate
key: /etc/daos/certs/agent.key
# Use the given directory for creating unix domain sockets
#
# NOTE: Do not change this when running under systemd control. If it needs to
# be changed, then make sure that it matches the RuntimeDirectory setting
# in /usr/lib/systemd/system/daos_agent.service
#
# default: /var/run/daos_agent
#runtime_dir: /var/run/daos_agent

# Full path and name of the DAOS agent logfile.
# default: /tmp/daos_agent.log
log_file: /tmp/daos_agent.log

# Manually define the fabric interfaces and domains to be used by the agent,
# organized by NUMA node.
# If not defined, the agent will automatically detect all fabric interfaces and
# select appropriate ones based on the server preferences.
#
#fabric_ifaces:
#-
# numa_node: 0
# devices:
# -
# iface: ib0
# domain: mlx5_0
# -
# iface: ib1
# domain: mlx5_1
#-
# numa_node: 1
# devices:
# -
# iface: ib2
# domain: mlx5_2
# -
# iface: ib3
# domain: mlx5_3

Any assistance or insights into resolving this issue would be greatly appreciated. Thank you!

rfcomm ?

Salvatore Terress — Tue, 21 May 2024 19:37:00 GMT

I am looking for help to implement / test rfcomm - on Ubuntu Description: Ubuntu 22.04.4 LTS

When I type
rfcomm -a

I get this response

nov25-1@nov251-desktop:~$ rfcomm --a
nov25-1@nov251-desktop:~$

When I type

rfcomm -h
I get this

nov25-1@nov251-desktop:~$ rfcomm --h
RFCOMM configuration utility ver 5.64
Usage:
	rfcomm [options] <command> <dev>

Options:
	-i, --device [hciX|bdaddr]     Local HCI device or BD Address
	-h, --help                     Display help
	-r, --raw                      Switch TTY into raw mode
	-A, --auth                     Enable authentication
	-E, --encrypt                  Enable encryption
	-S, --secure                   Secure connection
	-C, --central                  Become the central of a piconet
	-L, --linger [seconds]         Set linger timeout
	-a                             Show all devices (default)

Commands:
	bind     <dev> <bdaddr> [channel]	Bind device
	release  <dev>                   	Release device
	show     <dev>                   	Show device
	connect  <dev> <bdaddr> [channel]	Connect device
	listen   <dev> [channel [cmd]]   	Listen
	watch    <dev> [channel [cmd]]   	Watch

nov25-1@nov251-desktop:~$

I am using this link

Ubuntu Manpage: rfcomm - RFCOMM configuration utility[^]

Any help would be greatly appreciated
Thanks

How to redirect command output - general reference wanted...

Salvatore Terress — Mon, 04 Mar 2024 20:15:00 GMT

<a href="https://man7.org/linux/man-pages/man3/system.3.html">system(3) - Linux manual page</a>[<a href="https://man7.org/linux/man-pages/man3/system.3.html" target="_blank" title="New Window">^</a>]

This is somewhat a dupe, so if it bothers you...( I am not allowed to give instructions ...)

I am asking for generic / general help in capturing Linux command output.

I am going to use this as an example:

system("hcitool dev | cut -sf3 ");

I know what is does - that is NOT of my concern..

I can see the result in (Qt) console...

I do not know HOW - what "hidden" code (std??) put
the actual result of the call onto console

and

how can I redirect such call for my purpose ?

I did RTFM for "system" and found NO references , or missed them,
on how to capture THE actual output of the command.

that said - what would be SUCCESSFUL phrase to ask Mrs Google to
give me a general Linux resource ( text book ?) to cover

"standard output / input / error "
and

how to figure out if the command uses

"standard output / input / error "

and how to access it in C/C++

..all this just for learning purpose

CHEERS
THANks

Bluetooth - dead end again...

Salvatore Terress — Fri, 23 Feb 2024 01:26:00 GMT

I have reached another dead end in my Bluetooth programming...
without getting into details - task works fine when performed in Linux terminal

, but fails to connect when run in C++ code.

After RTFM I found
"the error source" in "bluez " library, burred in few layers of undocumented code ...

So I am going back to "level" where I can control the
usage of "bluez" library...

That means to go back to

https://people.csail.mit.edu/albert/bluez-intro/c404.html[^]

My question
to the forum -

is there a C++ version of the above?
( I asked Mrs Google...)

Yes, the foundation would still be "bluez" library...but if I can
manage to convert the above to C++ it my be "some " progress.

Thanks very much for any constructive help.

3dDeconvolve coding

Sevinc Bayar — Thu, 18 Jan 2024 18:31:00 GMT

I have done the individual analysis on my data , now I m trying to run 3dDeconvolve code but it does not work at all. I dont know what is wrong.

hcitool numbering hcix

Salvatore Terress — Tue, 19 Dec 2023 00:15:00 GMT

I am using hcitool to identify local , attached to my PC via USB
Bluetooth adapters.

The actual command is "hcitool dev".
Most of the time I receive hci0 plus address.
Recently I started getting hci1.

If I attach two adapters
I receive
hci0
hcix

where hcix keeps increasing ( the x ) with each, same , hcitool dev command.

I am looking for way to keep the hci0 as hci0.

Thanks very much for your help, it is appreciated very much

how to use "whereis" recursively ?

Salvatore Terress — Tue, 28 Nov 2023 20:17:00 GMT

Simple , but Mrs Google gives " where space is "....and not "whereis"....

Academic question - what is basic Bluetooth Linux access ?

Salvatore Terress — Tue, 07 Nov 2023 14:48:00 GMT

This is NOT problem / does not requires code / details and answer.

Basic statement
"bluez" (library) is part of the Linux kernel.

Academic question:
what is the basic / fundamental access of Bluetooth to Linux kernel ?
Is bypassing "bluez / hci " the way ?

"bluez" library uses "hci" "commands" , other GUI applications / commands are "free to utilize bluez" ....

For example - Qt uses "bluez" but have no means to actually reset Bluetooth devices - it will access devices no longer near system....
so do other application(s) .

How to verify Bluetooth?

Salvatore Terress — Fri, 03 Nov 2023 01:15:00 GMT

I have "upgraded" to Ubuntu 23.04.
"Discovered"it is lacking Bluetooth.
Used this opportunity to test "verify Bluetooth " in my code using "bluetoothctl".
The command responds correctly , but "gets stuck "
in "Waiting to connect to bluetoothd...".

Used same command in "terminal" with same result.

Can somebody suggest similar command or "bluetoothctl"command option (timeout ?)so it does detect lack of Bluetooth, but does not get stuck.

Temporary , I do verify Bluetooth not working by looking for "Agent registered " failure - which is correct response when Bluetooth is OK, actually running. Then if it runs I can "exit" from command.

Help is much appreciated.

Thanks

nov25-1@nov251-desktop:~$ bluetoothctl 
Waiting to connect to bluetoothd...

Message Closed

Jeremy Falcon — Fri, 13 Oct 2023 17:59:00 GMT

Message Closed

Kidding, I just wanted in on the fun.

Jeremy Falcon

Shrinking root partiton

megaadam — Tue, 24 Jan 2023 11:27:00 GMT

On my home Linux box I want to shrink my root 1.8 TB partition (ext4). Even unmounted gparted says "1.8 TB minimum size". And the GUI, accordingly, refuses to shrink it.

Googling til the end of elephanting times led me to resize2f2 how dangerous is that, in your experience?
And just trying to wrap my head around it is there "one filesystem size and one partition size?"

I actually want to reinstall the OS, and have poor experiences of upgrading. I have 0.6 TB of data, that I want to copy to a non-boot partition. and do not fancy the idea of buying storage to be used for an hour or two only. So yes I admit I am cheap and lazy, and I will never ever install Linux with such monolithic partitioning.
Thanks : )

"If we don't change direction, we'll end up where we're going"