changing network speed to 1000Mb/s

I am trying to change the server uplink from 100Mb/s to 1000Mb/s

ethtool eth0 output

    # ethtool eth0
Settings for eth0:
        Supported ports: [ TP MII ]
        Supported link modes:   10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Supports auto-negotiation: Yes
        Advertised link modes:  10baseT/Half 10baseT/Full
                                100baseT/Half 100baseT/Full
                                1000baseT/Half 1000baseT/Full
        Advertised auto-negotiation: No
        Speed: 100Mb/s
        Duplex: Full
        Port: MII
        PHYAD: 0
        Transceiver: internal
        Auto-negotiation: off
        Supports Wake-on: pumbg
        Wake-on: g
        Current message level: 0x00000033 (51)
        Link detected: yes

ifcfg-eth0 output

cat /etc/sysconfig/network-scripts/ifcfg-eth0
# device: eth0
DEVICE=eth0
BOOTPROTO=static
BROADCAST=10.0.0.1
HWADDR=00:24:21:ef:34:7c
IPADDR=10.0.0.1
NETMASK=255.255.255.255
SCOPE="peer 10.0.0.1"

i execute the command

ethtool -s eth0 speed 1000 duplex full autoneg off

but nothing changed

You need four things to successfully auto negotiate to a Gbit link.

1. A NIC capable of that speed. From the output yours seems to be.
2. A switch capable of handling Gbit. Please check your switch capabilities.
3. A proper cable, category 5, 5e or 6. If you have older cable (e.g. cat3) then Gbit speeds will (actually: should) not work.
   a) Test this first with a new, known good cable between wall socket and network card.
   b)If that does not fix it, run a cable directly between the NIC and the switch. (If that suddenly works then you got old or improper wiring in your walls, between wall sockets and the switches).
4. No weird incompatibility problems between NIC and switch. Try the same port you are now using with a different network card (e.g. plug in a laptop with Gbit. See if that negotiates to gigabit link speeds. If it does not then you are likely checking the wrong component.).