network error

Issues related to configuring your network
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rraoof2
Posts: 4
Joined: 2020/03/17 22:59:28

network error

Post by rraoof2 » 2020/03/17 23:23:08

running on GUI mode

whenever I perform the ifdown/ifup commands my network is fine, no issues.
A few seconds later I get a notification that says the connection failed, i perform ip a and the ip address, gateway and mask are all missing

rraoof2
Posts: 4
Joined: 2020/03/17 22:59:28

Re: network error

Post by rraoof2 » 2020/03/18 01:52:45

IP A after ifdown/ifup

[root@localhost ~]# ip a
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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:50:56:37:4e:1a brd ff:ff:ff:ff:ff:ff
inet 172.16.42.70/26 brd 172.16.42.127 scope global noprefixroute ens33
valid_lft forever preferred_lft forever
inet6 fe80::250:56ff:fe37:4e1a/64 scope link
valid_lft forever preferred_lft forever
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
link/ether 52:54:00:28:48:99 brd ff:ff:ff:ff:ff:ff
inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000
link/ether 52:54:00:28:48:99 brd ff:ff:ff:ff:ff:ff


literally two seconds later, i get the error and ip a again

[root@localhost ~]# ip a
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: ens33: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast state UP group default qlen 1000
link/ether 00:50:56:37:4e:1a brd ff:ff:ff:ff:ff:ff
3: virbr0: <NO-CARRIER,BROADCAST,MULTICAST,UP> mtu 1500 qdisc noqueue state DOWN group default qlen 1000
link/ether 52:54:00:28:48:99 brd ff:ff:ff:ff:ff:ff
inet 192.168.122.1/24 brd 192.168.122.255 scope global virbr0
valid_lft forever preferred_lft forever
4: virbr0-nic: <BROADCAST,MULTICAST> mtu 1500 qdisc pfifo_fast master virbr0 state DOWN group default qlen 1000
link/ether 52:54:00:28:48:99 brd ff:ff:ff:ff:ff:ff

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TrevorH
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Re: network error

Post by TrevorH » 2020/03/18 02:01:25

What's in /var/log/messages at the time?
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rraoof2
Posts: 4
Joined: 2020/03/17 22:59:28

Re: network error

Post by rraoof2 » 2020/03/18 02:07:02

Mar 17 22:00:09 localhost NetworkManager[787]: <warn> [1584496809.4772] dhcp4 (ens33): request timed out
Mar 17 22:00:09 localhost NetworkManager[787]: <info> [1584496809.4776] dhcp4 (ens33): state changed unknown -> timeout
Mar 17 22:00:09 localhost NetworkManager[787]: <info> [1584496809.4811] dhcp4 (ens33): canceled DHCP transaction, DHCP client pid 3959
Mar 17 22:00:09 localhost NetworkManager[787]: <info> [1584496809.4811] dhcp4 (ens33): state changed timeout -> done
Mar 17 22:00:09 localhost NetworkManager[787]: <info> [1584496809.4813] device (ens33): state change: ip-config -> failed (reason 'ip-config-unavailable', sys-iface-state: 'managed')
Mar 17 22:00:09 localhost NetworkManager[787]: <info> [1584496809.4816] manager: NetworkManager state is now CONNECTED_LOCAL
Mar 17 22:00:09 localhost NetworkManager[787]: <warn> [1584496809.4817] device (ens33): Activation: failed for connection 'ens33'
Mar 17 22:00:09 localhost NetworkManager[787]: <info> [1584496809.4819] device (ens33): state change: failed -> disconnected (reason 'none', sys-iface-state: 'managed')
Mar 17 22:00:09 localhost avahi-daemon[777]: Withdrawing address record for fe80::250:56ff:fe37:4e1a on ens33.
Mar 17 22:00:09 localhost avahi-daemon[777]: Withdrawing address record for 172.16.42.70 on ens33.
Mar 17 22:00:09 localhost avahi-daemon[777]: Leaving mDNS multicast group on interface ens33.IPv4 with address 172.16.42.70.
Mar 17 22:00:09 localhost avahi-daemon[777]: Interface ens33.IPv4 no longer relevant for mDNS.
Mar 17 22:01:01 localhost systemd: Created slice User Slice of root.
Mar 17 22:01:01 localhost systemd: Started Session 4 of user root.
Mar 17 22:01:01 localhost systemd: Removed slice User Slice of root.
Mar 17 22:04:09 localhost systemd: Starting Cleanup of Temporary Directories...
Mar 17 22:04:09 localhost systemd: Started Cleanup of Temporary Directories.
Mar 17 22:05:09 localhost NetworkManager[787]: <info> [1584497109.5265] policy: auto-activating connection 'ens33' (b4af99aa-2a79-4fbf-80a9-2cbacd5a89a7)
Mar 17 22:05:09 localhost NetworkManager[787]: <info> [1584497109.5273] device (ens33): Activation: starting connection 'ens33' (b4af99aa-2a79-4fbf-80a9-2cbacd5a89a7)
Mar 17 22:05:09 localhost NetworkManager[787]: <info> [1584497109.5274] device (ens33): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed')
Mar 17 22:05:09 localhost NetworkManager[787]: <info> [1584497109.5276] manager: NetworkManager state is now CONNECTING
Mar 17 22:05:09 localhost NetworkManager[787]: <info> [1584497109.5278] device (ens33): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
Mar 17 22:05:09 localhost NetworkManager[787]: <info> [1584497109.5299] device (ens33): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
Mar 17 22:05:09 localhost NetworkManager[787]: <info> [1584497109.5305] dhcp4 (ens33): activation: beginning transaction (timeout in 45 seconds)
Mar 17 22:05:09 localhost NetworkManager[787]: <info> [1584497109.5805] dhcp4 (ens33): dhclient started with pid 4111
Mar 17 22:05:09 localhost avahi-daemon[777]: Joining mDNS multicast group on interface ens33.IPv4 with address 172.16.42.70.
Mar 17 22:05:09 localhost avahi-daemon[777]: New relevant interface ens33.IPv4 for mDNS.
Mar 17 22:05:09 localhost avahi-daemon[777]: Registering new address record for 172.16.42.70 on ens33.IPv4.
Mar 17 22:05:09 localhost dhclient[4111]: DHCPDISCOVER on ens33 to 255.255.255.255 port 67 interval 7 (xid=0x1298cfe3)
Mar 17 22:05:10 localhost avahi-daemon[777]: Registering new address record for fe80::250:56ff:fe37:4e1a on ens33.*.
Mar 17 22:05:16 localhost dhclient[4111]: DHCPDISCOVER on ens33 to 255.255.255.255 port 67 interval 7 (xid=0x1298cfe3)
Mar 17 22:05:23 localhost dhclient[4111]: DHCPDISCOVER on ens33 to 255.255.255.255 port 67 interval 19 (xid=0x1298cfe3)
Mar 17 22:05:42 localhost dhclient[4111]: DHCPDISCOVER on ens33 to 255.255.255.255 port 67 interval 8 (xid=0x1298cfe3)
Mar 17 22:05:50 localhost dhclient[4111]: DHCPDISCOVER on ens33 to 255.255.255.255 port 67 interval 9 (xid=0x1298cfe3)
Mar 17 22:05:51 localhost dbus[743]: [system] Activating via systemd: service name='net.reactivated.Fprint' unit='fprintd.service'
Mar 17 22:05:51 localhost systemd: Starting Fingerprint Authentication Daemon...
Mar 17 22:05:51 localhost dbus[743]: [system] Successfully activated service 'net.reactivated.Fprint'
Mar 17 22:05:51 localhost systemd: Started Fingerprint Authentication Daemon.
Mar 17 22:05:51 localhost journal: Some code accessed the property 'AuthList' on the module 'authList'. That property was defined with 'let' or 'const' inside the module. This was previously supported, but is not correct according to the ES6 standard. Any symbols to be exported from a module must be defined with 'var'. The property access will work as previously for the time being, but please fix your code anyway.
Mar 17 22:05:54 localhost dbus[743]: [system] Activating via systemd: service name='org.freedesktop.hostname1' unit='dbus-org.freedesktop.hostname1.service'
Mar 17 22:05:54 localhost systemd: Starting Hostname Service...
Mar 17 22:05:54 localhost dbus[743]: [system] Successfully activated service 'org.freedesktop.hostname1'
Mar 17 22:05:54 localhost systemd: Started Hostname Service.
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.2154] agent-manager: req[0x56255a7f0bc0, :1.66/org.gnome.Shell.NetworkAgent/1000]: agent registered
Mar 17 22:05:54 localhost NetworkManager[787]: <warn> [1584497154.4747] dhcp4 (ens33): request timed out
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4747] dhcp4 (ens33): state changed unknown -> timeout
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4771] dhcp4 (ens33): canceled DHCP transaction, DHCP client pid 4111
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4771] dhcp4 (ens33): state changed timeout -> done
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4774] device (ens33): state change: ip-config -> failed (reason 'ip-config-unavailable', sys-iface-state: 'managed')
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4776] manager: NetworkManager state is now CONNECTED_LOCAL
Mar 17 22:05:54 localhost NetworkManager[787]: <warn> [1584497154.4778] device (ens33): Activation: failed for connection 'ens33'
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4780] device (ens33): state change: failed -> disconnected (reason 'none', sys-iface-state: 'managed')
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4847] policy: auto-activating connection 'ens33' (b4af99aa-2a79-4fbf-80a9-2cbacd5a89a7)
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4849] device (ens33): Activation: starting connection 'ens33' (b4af99aa-2a79-4fbf-80a9-2cbacd5a89a7)
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4850] device (ens33): state change: disconnected -> prepare (reason 'none', sys-iface-state: 'managed')
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4852] manager: NetworkManager state is now CONNECTING
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4853] device (ens33): state change: prepare -> config (reason 'none', sys-iface-state: 'managed')
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.4871] device (ens33): state change: config -> ip-config (reason 'none', sys-iface-state: 'managed')
Mar 17 22:05:54 localhost avahi-daemon[777]: Withdrawing address record for fe80::250:56ff:fe37:4e1a on ens33.
Mar 17 22:05:54 localhost avahi-daemon[777]: Withdrawing address record for 172.16.42.70 on ens33.
Mar 17 22:05:54 localhost avahi-daemon[777]: Leaving mDNS multicast group on interface ens33.IPv4 with address 172.16.42.70.
Mar 17 22:05:54 localhost avahi-daemon[777]: Interface ens33.IPv4 no longer relevant for mDNS.
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.5214] dhcp4 (ens33): activation: beginning transaction (timeout in 45 seconds)
Mar 17 22:05:54 localhost NetworkManager[787]: <info> [1584497154.5487] dhcp4 (ens33): dhclient started with pid 4166
Mar 17 22:05:54 localhost avahi-daemon[777]: Joining mDNS multicast group on interface ens33.IPv4 with address 172.16.42.70.
Mar 17 22:05:54 localhost avahi-daemon[777]: New relevant interface ens33.IPv4 for mDNS.
Mar 17 22:05:54 localhost avahi-daemon[777]: Registering new address record for 172.16.42.70 on ens33.IPv4.
Mar 17 22:05:54 localhost dhclient[4166]: DHCPDISCOVER on ens33 to 255.255.255.255 port 67 interval 5 (xid=0x47f0475b)
Mar 17 22:05:55 localhost avahi-daemon[777]: Registering new address record for fe80::250:56ff:fe37:4e1a on ens33.*.
Mar 17 22:05:59 localhost dhclient[4166]: DHCPDISCOVER on ens33 to 255.255.255.255 port 67 interval 9 (xid=0x47f0475b)

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jlehtone
Posts: 3101
Joined: 2007/12/11 08:17:33
Location: Finland

Re: network error

Post by jlehtone » 2020/03/20 08:55:31

NetworkManager manages your connections.

Do not call ifup/ifdown. Tell the NM to do the chores on your behalf.

If you don't want NM, then get rid of it, completely.

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