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VPS Have no network connection [message #26829]

Sat, 02 February 2008 13:20

Dediwebspace
Messages: 8
Registered: October 2007

Junior Member

Hi

On thursday our VPS node lost connection. The techs got it back online however since then none of the VE's have had a network connection.

Kernel:

Quote:

2.6.18-8.1.8.el5.028stab039.1 #1 SMP Mon Jul 23 18:02:32 MSD 2007 x86_64 x86_64 x86_64 GNU/Linux

Here is the sysctl.conf:

Quote:

# Kernel sysctl configuration file for Red Hat Linux
#
# For binary values, 0 is disabled, 1 is enabled. See sysctl( Cool

and
# sysctl.conf(5) for more details.

# Controls IP packet forwarding
net.ipv4.ip_forward = 1

# Controls source route verification
net.ipv4.conf.default.rp_filter = 1

# Do not accept source routing
net.ipv4.conf.default.accept_source_route = 0

# Controls the System Request debugging functionality of the kernel
kernel.sysrq = 0

# Controls whether core dumps will append the PID to the core filename
# Useful for debugging multi-threaded applications
kernel.core_uses_pid = 1

# Controls the use of TCP syncookies
net.ipv4.tcp_syncookies = 1

# Controls the maximum size of a message, in bytes
kernel.msgmnb = 65536

# Controls the default maxmimum size of a mesage queue
kernel.msgmax = 65536

# Controls the maximum shared segment size, in bytes
kernel.shmmax = 68719476736

# Controls the maximum number of shared memory segments, in pages
kernel.shmall = 4294967296
net.ipv4.ip_conntrack_max=32760

Output from service network restart:

Quote:

service network restart
Shutting down interface eth0: [ OK ]
Shutting down loopback interface: [ OK ]
Disabling IPv4 packet forwarding: net.ipv4.ip_forward = 0
[ OK ]
Bringing up loopback interface: [ OK ]
Bringing up interface eth0: [ OK ]

The node is an E4500 with 3GB RAM and 160GB RAID 1 drive setup

Thanks,

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Re: VPS Have no network connection [message #26862 is a reply to message #26829]

Mon, 04 February 2008 09:20

maratrus
Messages: 1495
Registered: August 2007
Location: Moscow

Senior Member

Hi,

Can you please show the output of the following commands:

- "ip a l" (from HN)
- "service vz status" (from HN)
- lsmod | grep vz (from HN)

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Re: VPS Have no network connection [message #26876 is a reply to message #26829]

Mon, 04 February 2008 16:12

Dediwebspace
Messages: 8
Registered: October 2007

Junior Member

Quote:

[root@server ~]# service vz status
OpenVZ is running...

Quote:

[root@server ~]# ip a l
2: lo: <LOOPBACK,UP,LOWER_UP> mtu 16436 qdisc noqueue
link/loopback 00:00:00:00:00:00 brd 00:00:00:00:00:00
inet 127.0.0.1/8 scope host lo
inet6 ::1/128 scope host
valid_lft forever preferred_lft forever
4: eth0: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 qdisc pfifo_fast qlen 1000
link/ether 00:08:a1:ab:8e:18 brd ff:ff:ff:ff:ff:ff
inet 66.197.149.119/25 brd 66.197.149.127 scope global eth0
inet6 fe80::208:a1ff:feab:8e18/64 scope link
valid_lft forever preferred_lft forever
6: sit0: <NOARP> mtu 1480 qdisc noop
link/sit 0.0.0.0 brd 0.0.0.0
1: venet0: <BROADCAST,POINTOPOINT,NOARP,UP,LOWER_UP> mtu 1500 qdisc noqueue
link/void

Quote:

[root@server ~]# lsmod | grep vz
vznetdev 55168 12
vzethdev 45584 0
vzrst 162344 0
vzcpt 141624 0
vzdquota 76392 6 [permanent]
vzmon 79248 10 vznetdev,vzethdev,vzrst,vzcpt
vzdev 36872 6 vznetdev,vzethdev,vzdquota,vzmon
ip_nat 53264 3 vzrst,ip_nat_ftp,iptable_nat
ip_conntrack 100884 12 vzrst,vzcpt,ip_nat_ftp,iptable_nat,ip_nat,xt_state
ipv6 420832 93 vzrst,vzcpt,vzmon

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Re: VPS Have no network connection [message #26881 is a reply to message #26876]

Mon, 04 February 2008 17:43

maratrus
Messages: 1495
Registered: August 2007
Location: Moscow

Senior Member

Hi,

Can you please describe more clearly your configuration:
- Do your VPSes use the public IPs?
- You cannot ping anything from inside the VPS and vice versa. Is it true?
- Please check the routing table?
- Check firewall rules?
- Please use "tcpdump" to look after the packets behavior.

And please if it is possible show the output of:
"ls /etc/sysconfig/network-scripts/"

Thank You!

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Re: VPS Have no network connection [message #26884 is a reply to message #26881]

Mon, 04 February 2008 17:54

Dediwebspace
Messages: 8
Registered: October 2007

Junior Member

Hi

The VPS use public IP's

They can ping the host node but cannot ping outside of it

Routing:

Quote:

route -n
Kernel IP routing table
Destination Gateway Genmask Flags Metric Ref Use Iface
64.191.50.57 0.0.0.0 255.255.255.255 UH 0 0 0 venet0
66.197.149.11 0.0.0.0 255.255.255.255 UH 0 0 0 venet0
64.191.50.56 0.0.0.0 255.255.255.255 UH 0 0 0 venet0
64.191.50.58 0.0.0.0 255.255.255.255 UH 0 0 0 venet0
66.197.149.68 0.0.0.0 255.255.255.255 UH 0 0 0 venet0
66.197.220.233 0.0.0.0 255.255.255.255 UH 0 0 0 venet0
64.191.50.55 0.0.0.0 255.255.255.255 UH 0 0 0 venet0
64.191.50.23 0.0.0.0 255.255.255.255 UH 0 0 0 venet0
64.191.50.100 0.0.0.0 255.255.255.255 UH 0 0 0 venet0
64.191.50.54 0.0.0.0 255.255.255.255 UH 0 0 0 venet0
66.197.149.0 0.0.0.0 255.255.255.128 U 0 0 0 eth0
169.254.0.0 0.0.0.0 255.255.0.0 U 0 0 0 eth0
0.0.0.0 66.197.149.1 0.0.0.0 UG 0 0 0 eth0

We have checked the firewall rules and disabled it also and flused IP Tables.

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Re: VPS Have no network connection [message #26885 is a reply to message #26884]

Mon, 04 February 2008 18:02

maratrus
Messages: 1495
Registered: August 2007
Location: Moscow

Senior Member

Hi,

and if possible
- "ls /etc/sysconfig/network-scripts/"?
- investigation with "tcpdump"
* are requests go out from VPS
* are they appear at HN
* are replies come to HN?

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Re: VPS Have no network connection [message #26886 is a reply to message #26885]

Mon, 04 February 2008 18:31

Dediwebspace
Messages: 8
Registered: October 2007

Junior Member

ifdown-isdn ifup ifup-isdn ifup-tunnel
ifcfg-lo ifdown-post ifup-aliases ifup-plip ifup-venet
ifdown ifdown-ppp ifup-bnep ifup-plusb ifup-wireless
ifdown-bnep ifdown-routes ifup-eth ifup-post init.ipv6-global
ifdown-eth ifdown-sit ifup-ippp ifup-ppp net.hotplug
ifdown-ippp ifdown-sl ifup-ipsec ifup-routes network-functions
ifdown-ipsec ifdown-tunnel ifup-ipv6 ifup-sit network-functions-ipv6
ifdown-ipv6 ifdown-venet ifup-ipx ifup-sl

Thats ls /etc/sysconfig/network-scripts/

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