#for i in `seq 271 350`; do ssh www$i "sed -i \"/servername\volumename/s/^/#/\" /etc/fstab"; done;
#
#for i in `seq 271 350`; do ssh www$i "umount -lf /mnt/servername/volumename"; done;
#comment entries in etc fstab
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Category Archives: One Liners
NetApp decode acp domain option
How does this option function to set a network? The acp.domain option is a convoluted decimal representation of the network portion of the IP address used for acp.
toaster*> options acp
acp.domain 65193
acp.enabled on
acp.netmask 65535
acp.port e0f
Take 65193 and convert it to binary: 1111111010101001. Then split it up into two (or more) octets: 11111110 10101001. Then convert each of the octets back to decimal: 254 169. Then reverse the order: 169 254. That is the acp network. The netmask portion is more straightforward. In this case our ACP network is 169.254/16.
You could hack a quick little one liner:
# for i in `echo "obase=2;65193" |bc | awk 'BEGIN{FS=""} {for(i=1;i<33;i++){printf $i; if(i==8)printf " ";}printf "\n"}'`; do echo "ibase=2;$i" |bc; done|tac | paste - - | sed 's/\t/./'
169.254
#Linux rebuild software RAID1
Set the bash field separator to newline:
IFS="
"
See what disk and partitions are currently up, then generate commands to re-add the missing disk and partitions, then run them:
for i in `cat /proc/mdstat | grep md | cut -d [ -f1 | sed -e 's/\(md[0-9]\).*\(sd[a-z][0-9]\)/mdadm --add \/dev\/\1 \/dev\/\2/' | sed -e 's/sdb/sda/'`; do eval $i; done;TODO: make it determine which disk to add (/dev/sda or /dev/sdb)
awk average multiple columns
If you have some output lined up in columns, use awk to average the columns. Here’s some sample output (from a NetApp “toaster> stats show -p flexscale-access”)
# cat sample.txt
73 5480 0 1040 84 0 0 0 0 0 0 0 541
73 6038 39 1119 84 0 0 0 0 0 0 0 475
73 5018 19 859 85 0 0 0 0 0 0 0 348
73 5960 20 1480 80 120 0 320 0 0 0 0 427
73 6098 0 1019 85 0 0 0 0 0 0 0 486
73 5220 0 1220 81 0 0 0 0 0 0 0 288
73 5758 79 1319 81 59 39 319 0 0 0 0 500
73 4419 0 2039 68 0 0 0 0 0 0 0 279
73 5400 0 840 86 0 0 0 0 0 0 0 382
73 5238 0 1299 80 0 0 0 0 0 0 0 389
73 5449 0 1696 76 59 0 199 0 0 0 0 340
73 5478 0 1419 79 0 0 0 0 0 0 0 414
73 5020 20 1000 83 0 0 0 0 0 0 0 405
73 4359 0 1059 80 0 0 0 0 0 0 0 295
73 5838 39 1139 83 0 19 0 0 0 0 0 494
73 6100 40 1720 78 0 0 0 0 0 0 0 480
73 5398 19 1239 81 0 0 0 0 0 0 0 398
73 5089 79 1097 82 0 0 0 0 0 0 0 459
73 6178 19 1159 84 0 39 159 0 0 0 0 487
73 4999 0 1239 80 0 0 0 0 0 0 0 345
73 4820 0 880 84 0 0 0 0 0 0 0 339
73 5467 0 1177 82 0 0 0 0 0 0 0 413
73 4700 60 1480 76 0 0 0 0 0 0 0 337
#And the column averages:
# cat sample.txt | awk '{for (i=1;i<=NF;i++){a[i]+=$i;}} END {for (i=1;i<=NF;i++){printf "%.0f", a[i]/NR; printf "\t"};printf "\n"}'
73 5371 19 1241 81 10 4 43 0 0 0 0 405
#Here awk loops through each field in a row, and adds the value to an array (a[i]) with the key being the field number. Then at the end, it takes the total, and divides by the number of rows (NR) and prints that (without decimals). It separates each field by a tab (\t) and after the end record prints a newline (\n).
You could make it print totals, as well as averages. You could also make it print out the original data, or a field header to know what each column represents...
get current client IP addresses from web farm
To see what common IPs are connecting to your web farm, ssh to all of the servers and get a list of clients. Then sort it until you see most busy clients.
# for i in `seq 401 436`; do ssh www$i "netstat -natp | grep EST | grep apa | grep ":80 "| awk '{print \$5}' | cut -d : -f1"; done | sort | uniq -c | sort -nk1 | tail
3 10.0.0.1
3 10.0.0.10
3 10.245.34.2
4 10.29.45.89
5 10.111.111.111
5 10.239.234.234
5 10.1.1.1
5 10.2.2.2
6 10.3.3.3
10 10.100.100.100
#The list shows the number of connections, and the client IP.
monitor host for slow ping times
When there is intermittent network latency to a host, it’s important to monitor a it for a pattern. Using ping can help narrow down what is causing the latency. VMWare load, bandwidth limitations, employee work patterns, backups, and many other sources could be the cause of the latency.
while true; do j=`ping <slowhost> -i1 -c1 2>&1 | grep icmp_req | awk '{print $7}' | cut -d = -f2 | cut -d . -f1`; if [ $j -gt 30 ]; then date | tr '\n' ' '; echo $j; fi; sleep 1s; done;This does a ping every second, and if it’s over a threshold (30ms in this case) it is considered unacceptable and logged with date.
remove IPv6 address from interface
If you don’t want to have an IPv6 address on an interface, you can quickly remove it:
# ip addr show dev eth0
2: eth0: mtu 1500 qdisc pfifo_fast state UP qlen 1000
link/ether 00:0c:29:c2:fc:59 brd ff:ff:ff:ff:ff:ff
inet 10.210.0.141/16 brd 10.210.255.255 scope global eth0
inet6 fe80::20c:29ff:fec2:fc59/64 scope link
valid_lft forever preferred_lft forever Only get the address:
# ip addr show dev eth0 | grep inet6 | awk '{print $2}'
fe80::20c:29ff:fec2:fc59/64Remove it:
# ip -6 addr del `ip addr show dev eth0 | grep inet6 | awk '{print $2}'` dev eth0Or do it to many hosts:
for i in `seq 201 272`; do ssh www$i "ip -6 addr del \`ip addr show dev eth0 | grep inet6 | awk '{print \$2}'\` dev eth0"; done;drop messages in mailqueue from single sender
Drop all messages from the sender ‘nagios’:
# for i in `mailq | tail -n +2 | awk 'BEGIN { RS = "" } { if ($7== "nagios") print $1}'`; do postsuper -d $i; done;
postsuper: B60BF9FB69: removed
postsuper: Deleted: 1 message
postsuper: C3B429FB6F: removed
postsuper: Deleted: 1 message
postsuper: 0306C9FB87: removed
postsuper: Deleted: 1 message
postsuper: E3BC79FB7E: removed
postsuper: Deleted: 1 message
postsuper: B32EA9FB65: removed
(many more lines)
Gets the mailqueue, starts the output on line 2, skipping the first header line, if the sender equals ‘nagios’ then print the first field, which is the message id. Then use postsuper to drop the message identified by it’s id.
get vmware esxi cpu info
~ # vmwarevim-cmd hostsvc/hosthardware | grep -A10 cpuPkg | grep description
cpuPkg = (vim.host.CpuPackage) [
(vim.host.CpuPackage) {
dynamicType = ,
index = 0,
vendor = "intel",
hz = 2833433579,
busHz = 333345127,
description = "Intel(R) Xeon(R) CPU E5440 @ 2.83GHz",
threadId = (short) [
0,
1,
Here I get the info for 8 different machines to see if they all match:
for i in `seq 1 1 8`; do ssh vm30$i "vim-cmd hostsvc/hosthardware | grep -A10 cpuPkg | grep description"; done;This works on 4.1 and 5.1 versions.
find long file paths
Use find and awk to get directories with very long names.
find . -type d | awk '{ if (length($0) > 254) print}'