rsync - Aug 2017 - Clarifications on getting debug information when rsync freezes

Hi

I am having a problem with rsync freezing and I would like to collect the proper
information while the problem happens. However, I would like to ask some
clarifications.

rsync-debug
==========
I see references of using rsync-debug but I cannot figure out how to use it
*while* the rsync is stuck. If I understand from various replies in this email
list it must be given as an argument to rsync beforehand?

If I do not want to change something in my current rsync setup, would it be ok
to do sth like this on the destination machine:

# 1. find the ssh PID from the source IP
destination_machine $ sudo netstat -atlp | grep "192.168.23"
tcp        0     36 192.168.40.23:ssh       192.168.23.40:49187     ESTABLISHED
915/sshd: abc [priv

# 2. find all related processes
destination_machine $ sudo pstree --show-pids 915
sshd(915)───sshd(1079)───rsync(1082)───rsync(1085)

# 3. then strace these all these

netstat
======
In order to provide the proper netstat info, related to the PIDs involved would
something like this suffice (in the destination and source machines with the
proper PIDs)? Should I provide different options or filter the output
differently?

$ sudo netstat -antp | egrep "(1085|1082|1079|915)/"
tcp        0      0 192.168.40.23:22        192.168.23.40:49187     ESTABLISHED
915/sshd: adz [priv

Regards
Vangelis

On Wed 16 Aug 2017, Vangelis Katsikaros via rsync wrote:
> 
> I am having a problem with rsync freezing and I would like to collect the
proper information while the problem happens. However, I would like to ask some
clarifications.
> 
> rsync-debug
> ==========> 
> I see references of using rsync-debug but I cannot figure out how to use it
*while* the rsync is stuck. If I understand from various replies in this email
list it must be given as an argument to rsync beforehand?
> 
> If I do not want to change something in my current rsync setup, would it be
ok to do sth like this on the destination machine:
> 
> # 1. find the ssh PID from the source IP
> destination_machine $ sudo netstat -atlp | grep "192.168.23"
> tcp        0     36 192.168.40.23:ssh       192.168.23.40:49187    
ESTABLISHED 915/sshd: abc [priv
> 
> # 2. find all related processes
> destination_machine $ sudo pstree --show-pids 915
> sshd(915)───sshd(1079)───rsync(1082)───rsync(1085)
> 
> # 3. then strace these all these
Well, you'll miss anything leading up to the hang, but doing it this may
show something significant, but perhaps not.


Paul