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[SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 26th, '14, 21:03
by Parckwart
I have two PCs with Mageia 4 installed. Both don't reply to pinging. Actually I can't connect to them in any way because I can't SSH them aswell. However my router detects them...

Re: Mageia PCs don't reply to pings

PostPosted: Mar 26th, '14, 22:48
by doktor5000
Check if ICMP (echo request - ping) is enabled in the firewall, the same for ssh - https://doc.mageia.org/mcc/4/en/content ... ewall.html

Re: Mageia PCs don't reply to pings

PostPosted: Mar 27th, '14, 03:02
by jiml8
Also, of course, make sure ssh daemon is running.

Re: Mageia PCs don't reply to pings

PostPosted: Mar 27th, '14, 07:04
by wobo
I confirm not receiving pings nor sending pings with my laptop, not even with my gateway (router).
Pinging my router with my desktop works ok.

Both machines are MGA4, laptop is a new installation, desktop is an upgrade from MGA3. Which points to a change in settings (I never touched these settings before).

Re: Mageia PCs don't reply to pings

PostPosted: Mar 27th, '14, 09:13
by Parckwart
Enabling in firewall settings worked.

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 27th, '14, 10:08
by wobo
Not here :(
Checking firewall settings was the first I tried before I wrote my forum post.

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 27th, '14, 11:44
by nero
wobo wrote:Not here :(
Checking firewall settings was the first I tried before I wrote my forum post.


run that in a console and post result , so we can see your fw setup:

sudo iptables -L -n

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 27th, '14, 13:22
by wobo
I disabled firewall in total
Code: Select all
[root@marvin-1 wobo]# iptables -L -n
Chain INPUT (policy ACCEPT)
target     prot opt source               destination         

Chain FORWARD (policy ACCEPT)
target     prot opt source               destination         

Chain OUTPUT (policy ACCEPT)
target     prot opt source               destination

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 27th, '14, 13:25
by nero
uhmm so if it's not a fw problem there should be some problem in the network , the source and the destination of the ping are in the same segment ?

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 27th, '14, 13:30
by wobo
All 3 devices (desktop, laptop, router) are in the same net segment - the usual home net.

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 27th, '14, 17:45
by ITA84
This is only for ping responding, but do you have any custom net configuration options in /etc/sysctl.conf or /etc/sysctl.d/?

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 27th, '14, 17:48
by wobo
No, as long as it works I tend to leave all of those untouched.

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 31st, '14, 03:16
by ghmitch
Aside from firewall:

If /proc/sys/net/ipv4/icmp_echo_ignore_all is set to "1", that will inhibit pings.

If /etc/sysctl.conf contains "net.ipv4.icmp_echo_ignore_all = 1", that will inhibit pings.

And it looks like SELinux can also interfere with pings.

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 31st, '14, 09:54
by wobo
ghmitch wrote:If /etc/sysctl.conf contains "net.ipv4.icmp_echo_ignore_all = 1", that will inhibit pings.

Thanks, this was the culprit.
Leaves the question of who and when and why this was set to "1" - it used to be "0" until MGA3 (as I said, I never ever touched this kind of settings).

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 31st, '14, 21:12
by doktor5000
Hmmm, draknetcenter says that this settings is defined by the chosen security policy (msec)
https://doc.mageia.org/mcc/4/en/content ... ml#d4e1165

But either this is buggy, or something else is involved. I've ticked that box to disable ICMP, then quit, and then rerun draknetcenter, unticked the box and quit. No change in /etc/sysctl.conf and also the settings there do not reflect the settings from draknetcenter.

On further testing, draknetcenter writes it's settings to /etc/sysctl.d/51-drakx.conf
And by default /etc/sysctl.conf is ignored in Mageia 3 and 4: https://bugs.mageia.org/show_bug.cgi?id=12066

Re: [SOLVED] Mageia PCs don't reply to pings

PostPosted: Mar 31st, '14, 21:40
by wobo
doktor5000 wrote:And by default /etc/sysctl.conf is ignored in Mageia 3 and 4: https://bugs.mageia.org/show_bug.cgi?id=12066

Hmm, after I changed that setting (from "1" to "0") the machine does serve ping replies, this does not look "ignored".

Or something totally different happened at the same time ....