[CentOS] Networking problems with fresh install

Thu Feb 28 01:46:02 UTC 2008
Chuck Campbell <campbell at accelinc.com>

I just did a fresh install of centos 5.0 from cd, followed by yum update
which installed 399 packages.  No failures or errors that I can see.

I have three nics in the box, but am only setting up one at the moment.

The box can ping others in my network, but if I try ssh, telnet, ftp, etc
I get this:

[root at cm network-scripts]# ftp watchdog
ftp: connect: No route to host
ftp> 

[root at cm sysconfig]# ftp 172.17.2.242
ftp: connect: No route to host


root at cm network-scripts]# telnet watchdog
Trying 172.17.2.242...
telnet: connect to address 172.17.2.242: No route to host
telnet: Unable to connect to remote host: No route to host

[root at cm network-scripts]# ssh -l campbell watchdog
ssh: connect to host watchdog port 22: No route to host

The weird part is I can do this:

[root at cm network-scripts]# ping watchdog
PING watchdog (172.17.2.242) 56(84) bytes of data.
64 bytes from watchdog (172.17.2.242): icmp_seq=1 ttl=64 time=0.170 ms
64 bytes from watchdog (172.17.2.242): icmp_seq=2 ttl=64 time=0.145 ms
64 bytes from watchdog (172.17.2.242): icmp_seq=3 ttl=64 time=0.135 ms

--- watchdog ping statistics ---
3 packets transmitted, 3 received, 0% packet loss, time 1998ms
rtt min/avg/max/mdev = 0.135/0.150/0.170/0.014 ms


[root at cm network-scripts]# arp watchdog
Address                  HWtype  HWaddress           Flags Mask            Iface
watchdog                 ether   00:16:76:D1:67:F2   C                     eth0

and I can do this:
[root at cm sysconfig]# ssh -l campbell cs1
campbell at cs1's password: ....................
and it will connect fine.


output of netstat -rn:

[root at cm network-scripts]# netstat -rn
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
172.17.2.0      0.0.0.0         255.255.255.0   U         0 0          0 eth0
192.168.122.0   0.0.0.0         255.255.255.0   U         0 0          0 virbr0
169.254.0.0     0.0.0.0         255.255.0.0     U         0 0          0 eth0
0.0.0.0         172.17.2.1      0.0.0.0         UG        0 0          0 eth0

output of netstat -r:

[root at cm network-scripts]# netstat -r
Kernel IP routing table
Destination     Gateway         Genmask         Flags   MSS Window  irtt Iface
172.17.2.0      *               255.255.255.0   U         0 0          0 eth0
192.168.122.0   *               255.255.255.0   U         0 0          0 virbr0
169.254.0.0     *               255.255.0.0     U         0 0          0 eth0
default         gateway         0.0.0.0         UG        0 0          0 eth0

output of route:

[root at cm network-scripts]# route
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface
172.17.2.0      *               255.255.255.0   U     0      0        0 eth0
192.168.122.0   *               255.255.255.0   U     0      0        0 virbr0
169.254.0.0     *               255.255.0.0     U     0      0        0 eth0
default         gateway         0.0.0.0         UG    0      0        0 eth0

here are the relevant files as far as I know:

/etc/hosts
[root at cm network-scripts]# more /etc/hosts
# Do not remove the following line, or various programs
# that require network functionality will fail.
127.0.0.1       localhost.localdomain   localhost
::1     localhost6.localdomain6 localhost6
172.17.2.1      gateway gateway.inexs.com
172.17.2.50     cm      cm.inexs.com
#172.17.2.52    cm2     cm2.inexs.com
172.17.2.51     cs1     cs1.inexs.com
#172.17.2.53    cs2     cs2.inexs.com
172.17.2.137    ingrid  ingrid.inexs.com
172.17.2.161    vail	vail.inexs.com
172.17.2.162    beaver  beaver.inexs.com
172.17.2.175    plotting        plotting.inexs.com
172.17.2.242    watchdog        watchdog.inexs.com

/etc/sysconfig/network-scripts/ifcfg-eth0
[root at cm network-scripts]# more ifcfg-eth0 
# Broadcom Corporation NetXtreme BCM5704 Gigabit Ethernet
DEVICE=eth0
BOOTPROTO=none
BROADCAST=172.17.2.255
HWADDR=00:e0:81:2c:73:86
ONBOOT=yes
DHCP_HOSTNAME=cm
TYPE=Ethernet
IPADDR=172.17.2.50
NETMASK=255.255.255.0
NETWORK=172.17.2.0
GATEWAY=172.17.2.1
USERCTL=yes
IPV6INIT=no
PEERDNS=no
PEERNTP=no

/etc/sysconfig/network-scripts/ifcfg-lo
[root at cm network-scripts]# more ifcfg-lo
DEVICE=lo
IPADDR=127.0.0.1
NETMASK=255.0.0.0
NETWORK=127.0.0.0
# If you're having problems with gated making 127.0.0.0/8 a martian,
# you can change this to something else (255.255.255.255, for example)
#BROADCAST=127.255.255.255
BROADCAST=255.255.255.255
ONBOOT=yes
NAME=loopback

output of ifconfig -a:
eth0      Link encap:Ethernet  HWaddr 00:E0:81:2C:73:86  
          inet addr:172.17.2.50  Bcast:172.17.2.255  Mask:255.255.255.0
          inet6 addr: fe80::2e0:81ff:fe2c:7386/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:27358 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4252 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:2338646 (2.2 MiB)  TX bytes:620434 (605.8 KiB)

eth1      Link encap:Ethernet  HWaddr 00:E0:81:2C:73:87  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
          Interrupt:19 

eth2      Link encap:Ethernet  HWaddr 00:E0:81:2C:74:33  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

lo        Link encap:Local Loopback  
          inet addr:127.0.0.1  Mask:255.0.0.0
          inet6 addr: ::1/128 Scope:Host
          UP LOOPBACK RUNNING  MTU:16436  Metric:1
          RX packets:1828 errors:0 dropped:0 overruns:0 frame:0
          TX packets:1828 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:2737876 (2.6 MiB)  TX bytes:2737876 (2.6 MiB)

peth0     Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF  
          inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link
          UP BROADCAST RUNNING NOARP  MTU:1500  Metric:1
          RX packets:27358 errors:0 dropped:0 overruns:0 frame:0
          TX packets:4255 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:1000 
          RX bytes:2448018 (2.3 MiB)  TX bytes:640420 (625.4 KiB)
          Interrupt:18 

sit0      Link encap:IPv6-in-IPv4  
          NOARP  MTU:1480  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

veth1     Link encap:Ethernet  HWaddr 00:00:00:00:00:00  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

veth2     Link encap:Ethernet  HWaddr 00:00:00:00:00:00  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

veth3     Link encap:Ethernet  HWaddr 00:00:00:00:00:00  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

vif0.0    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF  
          inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link
          UP BROADCAST RUNNING NOARP  MTU:1500  Metric:1
          RX packets:4252 errors:0 dropped:0 overruns:0 frame:0
          TX packets:27358 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:620434 (605.8 KiB)  TX bytes:2338646 (2.2 MiB)

vif0.1    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

vif0.2    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

vif0.3    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)
vif0.0    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF  
          inet6 addr: fe80::fcff:ffff:feff:ffff/64 Scope:Link
          UP BROADCAST RUNNING NOARP  MTU:1500  Metric:1
          RX packets:4252 errors:0 dropped:0 overruns:0 frame:0
          TX packets:27358 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:620434 (605.8 KiB)  TX bytes:2338646 (2.2 MiB)

vif0.1    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

vif0.2    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

vif0.3    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF  
          BROADCAST MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:0 (0.0 b)

virbr0    Link encap:Ethernet  HWaddr 00:00:00:00:00:00  
          inet addr:192.168.122.1  Bcast:192.168.122.255  Mask:255.255.255.0
          inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link
          UP BROADCAST RUNNING MULTICAST  MTU:1500  Metric:1
          RX packets:0 errors:0 dropped:0 overruns:0 frame:0
          TX packets:40 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:0 (0.0 b)  TX bytes:8674 (8.4 KiB)

xenbr0    Link encap:Ethernet  HWaddr FE:FF:FF:FF:FF:FF  
          inet6 addr: fe80::200:ff:fe00:0/64 Scope:Link
          UP BROADCAST RUNNING NOARP  MTU:1500  Metric:1
          RX packets:21327 errors:0 dropped:0 overruns:0 frame:0
          TX packets:0 errors:0 dropped:0 overruns:0 carrier:0
          collisions:0 txqueuelen:0 
          RX bytes:1523795 (1.4 MiB)  TX bytes:0 (0.0 b)


/etc/sysconfig/network
[root at cm sysconfig]# more network
NETWORKING=yes
NETWORKING_IPV6=no
HOSTNAME=cm


/etc/resolv.conf
[root at cm sysconfig]# more /etc/resolv.conf
nameserver 216.201.128.10
nameserver 66.196.216.10


/etc/sysconfig/iptables
[root at cm sysconfig]# more iptables
# Firewall configuration written by system-config-securitylevel
# Manual customization of this file is not recommended.
*filter
:INPUT ACCEPT [0:0]
:FORWARD ACCEPT [0:0]
:OUTPUT ACCEPT [0:0]
:RH-Firewall-1-INPUT - [0:0]
-A INPUT -j RH-Firewall-1-INPUT
-A FORWARD -j RH-Firewall-1-INPUT
-A RH-Firewall-1-INPUT -i lo -j ACCEPT
-A RH-Firewall-1-INPUT -p icmp --icmp-type any -j ACCEPT
-A RH-Firewall-1-INPUT -p 50 -j ACCEPT
-A RH-Firewall-1-INPUT -p 51 -j ACCEPT
-A RH-Firewall-1-INPUT -p udp --dport 5353 -d 224.0.0.251 -j ACCEPT
-A RH-Firewall-1-INPUT -p udp -m udp --dport 631 -j ACCEPT
-A RH-Firewall-1-INPUT -p tcp -m tcp --dport 631 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state ESTABLISHED,RELATED -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 21 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 25 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 2049 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 22 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m udp -p udp --dport 137 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m udp -p udp --dport 138 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 139 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 445 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 443 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 23 -j ACCEPT
-A RH-Firewall-1-INPUT -m state --state NEW -m tcp -p tcp --dport 80 -j ACCEPT
-A RH-Firewall-1-INPUT -j REJECT --reject-with icmp-host-prohibited
COMMIT



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