I have just detected that in one of my hosts (this is a virtual machine run by a cloud provider) there is a process eating up some bandwidth:
NetHogs version 0.6.0 PID USER PROGRAM DEV SENT RECEIVED 4617 root iscsid eth0 170.808 7.957 KB/sec 13300 root sshd: user1 [priv] eth0 0.000 0.841 KB/sec 26042 nagios ssh eth0 0.745 0.789 KB/sec TOTAL 171.656 10.287 KB/sec
I have googled a bit about this iscsid process (new thing to me), and it seems this is a kind of "SCSI over TCP" daemon. Fine with that. I have some questions:
- Why is this process using bandwidth continuously?
- I would like to know what is being mounted using the iSCSI protocol.
- What tools are there to get information about iSCSI configuration, mount points, ...
- Is the whole disk "mounted" via iSCSI, or just a partition, or what?
- Do I have a "disk" in my VM? The way I have myself setup virtual machines (with XEN) has always been using .qcow2 files in the host filesystem.
- If there is no disk, how is the VM booting?
Mount offers no clues about it.
mount /dev/sda1 on / type ext3 (rw,noatime,nodiratime,errors=remount-ro) proc on /proc type proc (rw,noexec,nosuid,nodev) /sys on /sys type sysfs (rw,noexec,nosuid,nodev) varrun on /var/run type tmpfs (rw,noexec,nosuid,nodev,mode=0755) varlock on /var/lock type tmpfs (rw,noexec,nosuid,nodev,mode=1777) udev on /dev type tmpfs (rw,mode=0755) devshm on /dev/shm type tmpfs (rw) devpts on /dev/pts type devpts (rw,gid=5,mode=620) /dev/sda2 on /home type ext3 (rw,noatime,nodiratime)
$ sudo iscsiadm -m session -P 0 tcp:  18.104.22.168:3260,1 iqn.2017-11.net.ovh:r44247vol0 $ sudo fdisk -l Disk /dev/uba: 4002 MB, 4002910208 bytes 32 heads, 63 sectors/track, 3878 cylinders Units = cylinders of 2016 * 512 = 1032192 bytes Disk identifier: 0x20fb6d2b Device Boot Start End Blocks Id System /dev/uba1 * 1 3878 3908992+ b W95 FAT32 Disk /dev/sda: 21.4 GB, 21474836480 bytes 64 heads, 32 sectors/track, 20480 cylinders Units = cylinders of 2048 * 512 = 1048576 bytes Disk identifier: 0x00003fd3 Device Boot Start End Blocks Id System /dev/sda1 * 3 5002 5118976+ 83 Linux Partition 1 does not end on cylinder boundary. /dev/sda2 5002 20001 15358976 83 Linux Partition 2 does not end on cylinder boundary. $ sudo dmesg | grep -A10 "iSCSI Init" (no output)
The output fdisk command is quite obscure to me: does this mean it is iSCSI related? I do not see any reference to iSCSI there ...