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< meta name = "cheatsheet for network administrators" >
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< title > networking cheat sheet< / title >
< / head >
< body >
< r-grid columns = "1" columns-l = "1" >
< r-cell span = "row" >
< a href = "https://github.com/domeniko-gentner/network-cheatsheet" >
< img width = "32" height = "32" src = "/github.png" alt = "github logo" >
< / a >
< h1 > networking cheat sheet< / h1 >
< / r-cell >
< / r-grid >
< r-grid class = "panel" >
< r-cell >
< h2 > TOC< / h2 >
< ul >
< li > < a href = "#ethernet" > Ethernet Frame< / a > < / li >
< li > < a href = "#v4" > IpV4 Header< / a > < / li >
< li > < a href = "#v6" > IpV6 Header< / a > < / li >
< li > < a href = "#tcp" > TCP Header< / a > < / li >
< li > < a href = "#udp" > UDP Header< / a > < / li >
< li > < a href = "#tcpdump" > tcpdump< / a > < / li >
< li > < a href = "#nmap" > nmap< / a > < / li >
< li > < a href = "#mtr" > mtr< / a > < / li >
< li > < a href = "#iptables" > iptables< / a > < / li >
< li > < a href = "#cables" > Fibre Colors< / a > < / li >
< li > < a href = "#sfp" > SFP(+) speeds< / a > < / li >
< li > < a href = "#bgp" > BGP Table path selection< / a > < / li >
< / ul >
< / r-cell >
< / r-grid >
< r-grid columns = "1" class = "wrapper" >
< r-cell class = "panel" id = "ethernet" >
< h2 > Ethernet Frame< / h2 >
< r-grid columns = "9" class = "ethernet-frame-grid" >
< r-cell span = "1" data-tooltip title = "7 bytes<br>for synchronization" class = "ethernet-frame-cell" >
< p class = "frame-text" > Preamble< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "1 byte<br>Marks end of preamble and start of frame. Always 1." class = "ethernet-frame-cell" >
< p class = "frame-text" > SFD< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "6 bytes<br>destination address" class = "ethernet-frame-cell" >
< p class = "frame-text" > Dest. MAC< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "6 bytes<br>source address" class = "ethernet-frame-cell" >
< p class = "frame-text" > Source MAC< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "4 bytes<br>802.1Q, last 12 bits are VLAN ID, optional" class = "ethernet-frame-cell" >
< p class = "frame-text" > [VLAN]< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "2 bytes<br>0x8808: Flow Control<br>0x8809: LACP<br>0x8000: IPV4,<br>0x8100: Tagged VLAN<br>0x8060: ARP<br>0x86DD: IPV6" class = "ethernet-frame-cell" >
< p class = "frame-text" > EtherType< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "46-1500 bytes<br>can be bigger for jumbo frames" class = "ethernet-frame-cell" >
< p class = "frame-text" > Payload< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "4 bytes<br>FCS/Checksum of the frame" class = "ethernet-frame-cell" >
< p class = "frame-text" > FCS< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "4 bytes<br>gap between frames<br>uses a timed pause equal to 4 bytes" class = "ethernet-frame-cell" >
< p class = "frame-text" > GAP< / p >
< / r-cell >
< / r-grid >
< / r-cell >
< r-cell class = "panel" id = "v4" >
< h2 > IPV4 Header< / h2 >
< r-grid columns = "8" class = "ethernet-frame-grid" >
< r-cell span = "1-2" data-tooltip title = "4 bits<br>Protocol version, equals 4" class = "ethernet-frame-cell" >
< p class = "frame-text" > IP version< / p >
< / r-cell >
< r-cell span = "3-4" data-tooltip title = "4 bits<br>Number of 32 bit words in the header<br>5 x 32b = 160b = 20B" class = "ethernet-frame-cell" >
< p class = "frame-text" > Header Length< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "6 bits<br>Service Type (QOS)<br>Expedited Forwarding: 101110<br>Best Effort: 000000" class = "ethernet-frame-cell" >
< p class = "frame-text" > DSCP< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "2 bits<br>Explicit Congestion Notification<br>Requires support on both ends" class = "ethernet-frame-cell" >
< p class = "frame-text" > ECN< / p >
< / r-cell >
< r-cell span = "7-8" data-tooltip title = "16 bits<br>Total Length of the header<br>Min size: 20B<br>Max size: 65535B" class = "ethernet-frame-cell" >
< p class = "frame-text" > Total Length< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "8" class = "ethernet-frame-grid" >
< r-cell span = "1-4" data-tooltip title = "16 bits<br>Unique ID, identifies datagram parts.<br>" class = "ethernet-frame-cell" >
< p class = "frame-text" > Identification< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "3 bits<br>First: must be zero<br>Second: no fragments<br>Third: more fragments follow" class = "ethernet-frame-cell" >
< p class = "frame-text" > Flags< / p >
< / r-cell >
< r-cell span = "6-8" data-tooltip title = "13 bits<br>Byte offset of a fragment, relative to first" class = "ethernet-frame-cell" >
< p class = "frame-text" > Fragment Offset< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "8" class = "ethernet-frame-grid" >
< r-cell span = "1-2" data-tooltip title = "8 bits<br>Amount of hops the package lives" class = "ethernet-frame-cell" >
< p class = "frame-text" > TTL< / p >
< / r-cell >
< r-cell span = "3-4" data-tooltip title = "8 bits<br>Transport Layer Protocol<br>0x01: ICMP<br>0x06: TCP<br>0x11: UDP<br>0x12: MUX<br>" class = "ethernet-frame-cell" >
< p class = "frame-text" > Protocol< / p >
< / r-cell >
< r-cell span = "5-8" data-tooltip title = "16 bits" class = "ethernet-frame-cell" >
< p class = "frame-text" > Header Checksum< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "8" class = "ethernet-frame-grid" >
< r-cell span = "row" data-tooltip title = "32 bits<br>Source IPv4 Address" class = "ethernet-frame-cell" >
< p class = "frame-text" > Source address< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "8" class = "ethernet-frame-grid" >
< r-cell span = "1-8" data-tooltip title = "32 bits<br>Destination IPv4 Address" class = "ethernet-frame-cell" >
< p class = "frame-text" > Destination address< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "8" class = "ethernet-frame-grid" >
< r-cell span = "1-8" data-tooltip title = "32 bits<br>Various options, rarely used" class = "ethernet-frame-cell" >
< p class = "frame-text" > Options< / p >
< / r-cell >
< / r-grid >
< / r-cell > <!-- IPV4 Header -->
< r-cell class = "panel" id = "v6" >
< h2 > IPv6 Header< / h2 >
< r-grid columns = "8" class = "ethernet-frame-grid" >
< r-cell span = "1-2" data-tooltip title = "4 bits<br>IP Version -> 0110 = 6" class = "ethernet-frame-cell" >
< p class = "frame-text" > Version< / p >
< / r-cell >
< r-cell span = "3-4" data-tooltip title = "8 bits<br>See DSCP and ECN on IPV4" class = "ethernet-frame-cell" >
< p class = "frame-text" > Traffic Class< / p >
< / r-cell >
< r-cell span = "5-8" data-tooltip title = "20 bits<br>Sequential Flow" class = "ethernet-frame-cell" >
< p class = "frame-text" > Flow Label< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "8" class = "ethernet-frame-grid" >
< r-cell span = "1-4" data-tooltip title = "16 bits<br>Payload length may exceed 65535, in which case it is 0" class = "ethernet-frame-cell" >
< p class = "frame-text" > Payload Length< / p >
< / r-cell >
< r-cell span = "5-6" data-tooltip title = "8 bits<br>indicates protocol, same identifiers as V4" class = "ethernet-frame-cell" >
< p class = "frame-text" > Next header< / p >
< / r-cell >
< r-cell span = "7-8" data-tooltip title = "8 bits<br>indicates protocol, same identifiers as V4" class = "ethernet-frame-cell" >
< p class = "frame-text" > TTL< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "8" class = "ethernet-frame-grid" >
< r-cell span = "row" data-tooltip title = "128 bits<br>Source Address" class = "ethernet-frame-cell" >
< p class = "frame-text" > Source Address< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "8" class = "ethernet-frame-grid" >
< r-cell span = "row" data-tooltip title = "128 bits<br>Destination Address" class = "ethernet-frame-cell" >
< p class = "frame-text" > Destination address< / p >
< / r-cell >
< / r-grid >
< / r-cell > <!-- IPV6 Header -->
< r-cell class = "panel" id = "tcp" >
< h2 > TCP Header< / h2 >
< r-grid columns = "16" class = "ethernet-frame-grid" >
< r-cell span = "1-8" data-tooltip title = "16 bits<br>Port segment was sent from" class = "ethernet-frame-cell" >
< p class = "frame-text" > Source port< / p >
< / r-cell >
< r-cell span = "9-16" data-tooltip title = "16 bits<br>Port segmnent is sent to" class = "ethernet-frame-cell" >
< p class = "frame-text" > Destination port< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "1" class = "ethernet-frame-grid" >
< r-cell span = "row" data-tooltip title = "32 bits<br>If SYN flag is set, this is the initial packet.<br>If SYN is not set, data is at number+1" class = "ethernet-frame-cell" >
< p class = "frame-text" > Sequence number< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "1" class = "ethernet-frame-grid" >
< r-cell span = "row" data-tooltip title = "32 bits<br>If the ACK flag is set,<br>then the value of this field is the next<br>sequence number that the sender of the ACK is expecting." class = "ethernet-frame-cell" >
< p class = "frame-text" > Acknowledgment number< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "16" class = "ethernet-frame-grid" >
< r-cell span = "1-2" data-tooltip title = "4 bits<br>Number of 32 bit words that define the size of the header." class = "ethernet-frame-cell" >
< p class = "frame-text" > Data offset< / p >
< / r-cell >
< r-cell span = "3-4" data-tooltip title = "3 bits<br>Reserved for future use." class = "ethernet-frame-cell" >
< p class = "frame-text" > Reserved< / p >
< / r-cell >
< r-cell span = "5-9" data-tooltip title = "9 bits<br>SYN: synchronize, start of connection<br>ACK: acknowledge, confirm connection<br>RST: reset connection<br>FIN: last package from sender<br>URG: urgent bit is significant<br>CWR: congestion window reduced" class = "ethernet-frame-cell" >
< p class = "frame-text" > Flags< / p >
< / r-cell >
< r-cell span = "10-16" data-tooltip title = "16 bits<br>Number of bytes the sender of this segment is willing to receive" class = "ethernet-frame-cell" >
< p class = "frame-text" > Window size< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "2" class = "ethernet-frame-grid" >
< r-cell span = "1" data-tooltip title = "16 bits<br>Used for error checking. TCP can resend invalid segments." class = "ethernet-frame-cell" >
< p class = "frame-text" > Checksum< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "16 bits<br>If the URG flag is set, then this 16-bit field is an offset from the sequence number indicating the last urgent data byte." class = "ethernet-frame-cell" >
< p class = "frame-text" > Urgent pointer< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "1" class = "ethernet-frame-grid" >
< r-cell span = "row" data-tooltip title = "0-320 bits<br>Optional options. Must be divisable by 32, otherwise 0 padding at the end." class = "ethernet-frame-cell" >
< p class = "frame-text" > Options< / p >
< / r-cell >
< / r-grid >
< / r-cell > <!-- TCP Header -->
< r-cell class = "panel" id = "udp" >
< h2 > UDP Header< / h2 >
< r-grid columns = "2" class = "ethernet-frame-grid" >
< r-cell span = "1" data-tooltip title = "16 bits<br>Port the datagram is sent from (optional in IPv6)." class = "ethernet-frame-cell" >
< p class = "frame-text" > Source Port< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "16 bits<br>Port the datagram is sent to." class = "ethernet-frame-cell" >
< p class = "frame-text" > Destination port< / p >
< / r-cell >
< / r-grid >
< r-grid columns = "2" class = "ethernet-frame-grid" >
< r-cell span = "1" data-tooltip title = "16 bits<br>Min Length: 8 bytes<br>Max length: 65535 bytes." class = "ethernet-frame-cell" >
< p class = "frame-text" > Length< / p >
< / r-cell >
< r-cell span = "1" data-tooltip title = "16 bits<br>Used for error recognition. Optional in V4, mandatatory in V6. All zeroes if unused." class = "ethernet-frame-cell" >
< p class = "frame-text" > Checksum< / p >
< / r-cell >
< / r-grid >
< / r-cell > <!-- UDP Header -->
< r-cell >
< r-grid columns = "10" class = "panel" id = "tcpdump" >
< r-cell span = "row" > < h2 > tcpdump< / h2 > < / r-cell >
< r-cell span = "row" > < h3 > flags< / h3 > < / r-cell >
< r-cell span = "1" data-tooltip title = "tcpdump -i eth0" > -i name< / r-cell > < r-cell span = "2-5" > Capture named interfaces, any for all< / r-cell >
< r-cell span = "6-6" data-tooltip title = "tcpdump -c10" > -c integer< / r-cell > < r-cell span = "7-10" > Capture amount of packages< / r-cell >
< r-cell span = "1" data-tooltip title = "tcpdump -D" > -D< / r-cell > < r-cell span = "2-5" > Show available interfaces< / r-cell >
< r-cell span = "6-6" data-tooltip title = "tcpdump -n -c10 -i any" > -n< / r-cell > < r-cell span = "7-10" > Do not resolve host-names< / r-cell >
< r-cell span = "1" data-tooltip title = "tcpdump -nn -c10 -i eth0" > -nn< / r-cell > < r-cell span = "2-5" > Do not resolve host-names or services (ports)< / r-cell >
< r-cell span = "6-6" data-tooltip title = "tcpdump -n -c10 -i eth0 tcp" > tcp< / r-cell > < r-cell span = "7-10" > Capture tcp< / r-cell >
< r-cell span = "1" data-tooltip title = "tcpdump -n -c10 -i eth0 tcp" > udp< / r-cell > < r-cell span = "2-5" > Capture udp, also works with others such as arp< / r-cell >
< r-cell span = "6-6" data-tooltip title = "tcpdump -n -c10 -i eth0 host 10.10.10.10 and [not] udp" > host IP< / r-cell > < r-cell span = "7-10" > Capture data to or from this host only< / r-cell >
< r-cell span = "1" data-tooltip title = "tcpdump -n -c10 -i eth0 src 10.10.10.10 and tcp" > src IP< / r-cell > < r-cell span = "2-5" > Capture data from this host only< / r-cell >
< r-cell span = "6-6" data-tooltip title = "tcpdump -n -c10 -i eth0 dst 10.10.10.10" > dst IP< / r-cell > < r-cell span = "7-10" > Capture data sent to this host only< / r-cell >
< r-cell span = "1" data-tooltip title = "tcpdump -n -c10 -i eth0 net 10.10.10.0/24" > net CIDR< / r-cell > < r-cell span = "2-5" > Capture data to or from this subnet< / r-cell >
< r-cell span = "6-6" data-tooltip title = "tcpdump -n -c10 -i eth0 host 10.10.10.10 and port 53" > port number< / r-cell > < r-cell span = "7-10" > Use service name instead of port< / r-cell >
< r-cell span = "1" data-tooltip title = "tcpdump -n -i eth0 port not ssh" > port not num|name< / r-cell > < r-cell span = "2-5" > Exclude port or service in report< / r-cell >
< r-cell span = "row" > < h3 > tcp flags< / h3 > < / r-cell >
< r-cell span = "1-2" > [S] SYNC< / r-cell >
< r-cell span = "3-4" > [.|A] ACKNOWLEDGE< / r-cell >
< r-cell span = "5-6" > [R] RESET< / r-cell >
< r-cell span = "7-8" > [F] FINISHED< / r-cell >
< r-cell span = "9-10" > [P] PUSH< / r-cell >
< r-cell span = "row" > Flags can be displayed combined, [S.] means sync and acknowledge< / r-cell >
< / r-grid > <!-- tcpdump -->
< / r-cell >
< r-cell >
< r-grid columns = "10" class = "panel" id = "nmap" >
< r-cell span = "row" > < h2 > nmap< / h2 > < / r-cell >
< r-cell span = "1" data-tooltip title = "nmap 10.10.10.1" > IP< / r-cell > < r-cell span = "2-5" > Scan host< / r-cell >
< r-cell span = "6-6" data-tooltip title = "nmap 10.10.10.1 10.10.10.2" > LIST< / r-cell > < r-cell span = "7-10" > Scan list< / r-cell >
< r-cell span = "1" data-tooltip title = "nmap 10.10.10.0/24" > CIDR< / r-cell > < r-cell span = "2-5" > Scan subnet< / r-cell >
< r-cell span = "6-6" data-tooltip title = "nmap -iL targets.txt" > -iL file< / r-cell > < r-cell span = "7-10" > Scan targets from file< / r-cell >
< r-cell span = "1" data-tooltip title = "nmap 10.10.10.0/24 -iR 100" > -iR number< / r-cell > < r-cell span = "2-5" > Random hosts of amount< / r-cell >
< r-cell span = "6-6" data-tooltip title = "nmap 10.10.10.0/24 --exclude 10.10.10.1 10.10.10.253" > --exclude< / r-cell > < r-cell span = "7-10" > Exclude hosts< / r-cell >
< r-cell span = "1" data-tooltip title = "nmap -iL targets.txt" > -iL file< / r-cell > < r-cell span = "2-5" > Scan targets from file< / r-cell >
< r-cell span = "6-6" data-tooltip title = "nmap -sU 10.10.10.1" > -sU< / r-cell > < r-cell span = "7-10" > UDP port scan< / r-cell >
< r-cell span = "1" data-tooltip title = "nmap -sU -n 10.10.10.1" > -n< / r-cell > < r-cell span = "2-5" > No DNS resolution< / r-cell >
< r-cell span = "6-6" data-tooltip title = "nmap -p- 10.10.10.1" > -p-< / r-cell > < r-cell span = "7-10" > Scan ALL ports from 0 to 65353< / r-cell >
< r-cell span = "1" data-tooltip title = "nmap -p 1-1023 -sU 10.10.10.1" > -p n[-n]< / r-cell > < r-cell span = "2-5" > Scan port or range< / r-cell >
< r-cell span = "6-6" data-tooltip title = "nmap -p U:53,T:80 10.10.10.1" > -p U:n,T:n< / r-cell > < r-cell span = "7-10" > Scan mixed ports, UDP and TCP< / r-cell >
< r-cell span = "1" data-tooltip title = "nmap -F 10.10.10.1" > -F< / r-cell > < r-cell span = "2-5" > Fast scan 100 ports< / r-cell >
< r-cell span = "6-6" data-tooltip title = "nmap -sV -p 443 10.10.10.1" > -sV< / r-cell > < r-cell span = "7-10" > Try to detect service< / r-cell >
< / r-grid > <!-- nmap -->
< / r-cell >
< r-cell >
< r-grid columns = "10" class = "panel" id = "mtr" >
< r-cell span = "row" > < h2 > mtr< / h2 > < / r-cell >
< r-cell span = "1" data-tooltip title = "mtr 10.10.10.1" > IP< / r-cell > < r-cell span = "2-5" > Run route to host< / r-cell >
< r-cell span = "6-6" data-tooltip title = "mtr -z 10.10.10.1" > -z< / r-cell > < r-cell span = "7-10" > Resolve ASN< / r-cell >
< r-cell span = "1" data-tooltip title = "mtr -c1 10.10.10.1" > -c num< / r-cell > < r-cell span = "2-5" > Run num cycles< / r-cell >
< r-cell span = "6-6" data-tooltip title = "mtr -r -z -c1 10.10.10.1" > -r< / r-cell > < r-cell span = "7-10" > Report mode, useful with -c< / r-cell >
< r-cell span = "1" data-tooltip title = "mtr -w 10.10.10.1" > -w< / r-cell > < r-cell span = "2-5" > Do not truncate network names aka wide mode< / r-cell >
< r-cell span = "6-6" data-tooltip title = "mtr -r -z -n -c1 10.10.10.1" > -n< / r-cell > < r-cell span = "7-10" > No RDNS< / r-cell >
< r-cell span = "1" data-tooltip title = "mtr -U 10.10.10.1" > -u< / r-cell > < r-cell span = "2-5" > use UDP instead of ICMP< / r-cell >
< r-cell span = "6-6" data-tooltip title = "mtr -T 10.10.10.1" > -T< / r-cell > < r-cell span = "7-10" > use TCP instead of ICMP< / r-cell >
< r-cell span = "1" data-tooltip title = "mtr -f2 10.10.10.1" > -f num< / r-cell > < r-cell span = "2-5" > set first TTL, useful for skipping own router< / r-cell >
< r-cell span = "6-6" data-tooltip title = "mtr -i 0.2 10.10.10.1" > -i float< / r-cell > < r-cell span = "7-10" > set interval, default is 1 second< / r-cell >
< / r-grid > <!-- mtr -->
< / r-cell >
< r-cell >
< r-grid columns = "10" class = "panel" id = "iptables" >
< r-cell span = "row" > < h2 > iptables< / h2 > < / r-cell >
< r-cell span = "1" data-tooltip title = "iptables -vL" > -vL< / r-cell > < r-cell span = "2-5" > Shows rules hit counters< / r-cell >
< r-cell span = "1" data-tooltip title = "iptables -A OUTPUT" > -A chain< / r-cell > < r-cell span = "7-10" > Append rule to chain< / r-cell >
< r-cell span = "1" data-tooltip title = "iptables -I INPUT 2" > -I chain num< / r-cell > < r-cell span = "2-5" > Insert rule to chain at position< / r-cell >
< r-cell span = "1" data-tooltip title = "iptables -I OUTPUT -s 10.10.10.0/24" > -s CIDR< / r-cell > < r-cell span = "7-10" > Packages from source< / r-cell >
< r-cell span = "1" data-tooltip title = "iptables -I INPUT -d 10.10.10.0/24" > -d CIDR< / r-cell > < r-cell span = "2-5" > Packages to destination< / r-cell >
< r-cell span = "1" data-tooltip title = "iptables -I INPUT -d 10.10.10.0/24 -j DROP" > -j target< / r-cell > < r-cell span = "7-10" > Apply target to rule< / r-cell >
< r-cell span = "1" data-tooltip title = "iptables -I INPUT -m mac --mac-source 00:00:00:FF:FF:FF" > -m extension< / r-cell > < r-cell span = "2-5" > Use an extension to match packet< / r-cell >
< r-cell span = "1" data-tooltip title = "iptables -L [-t tablename]" > -L< / r-cell > < r-cell span = "7-10" > List all rules, use -t for specific tables< / r-cell >
< r-cell span = "row" > < h3 > chains< / h3 > < / r-cell >
< r-cell span = "row" > A chain defines a set of rules. They do not need either a source nor a destination. They can be applied to those later.< / r-cell >
< r-cell data-tooltip title = "Sent in this context means,<br>directly sent via the interface<br>this rule applies to" span = "1-2" > OUTPUT - When a package is sent directly< / r-cell >
< r-cell span = "3-4" > INPUT - When a package is received< / r-cell >
< r-cell data-tooltip title = "Example: Using another virtual interface<br>for e.g. a virtual machine." span = "5-6" > FORWARD - When a package is forwarded< / r-cell >
< r-cell span = "7-10" > USER DEFINED - You can define a user defined chain and apply it to any source/destination.< / r-cell >
< / r-grid >
< / r-cell >
< r-cell >
< r-grid columns = "10" class = "panel" id = "cables" >
< r-cell span = "row" > < h2 > Fibre cables color coding< / h2 > < / r-cell >
< r-cell span = "1" style = "background-color: orange;" > < / r-cell > < r-cell span = "2-10" > OM1/2 multi-mode< / r-cell >
< r-cell span = "1" style = "background-color: aqua;" > < / r-cell > < r-cell span = "2-10" > OM3 multi-mode< / r-cell >
< r-cell span = "1" style = "background-color: #c4618c;" > < / r-cell > < r-cell span = "2-10" > OM4 multi-mode< / r-cell >
< r-cell span = "1" style = "background-color: lime" > < / r-cell > < r-cell span = "2-10" > OM5 multi-mode< / r-cell >
< r-cell span = "1" style = "background-color: yellow" > < / r-cell > < r-cell span = "2-10" > OS1/2 single-mode PC with a blue plug< / r-cell >
< r-cell span = "1" style = "background-color: yellow" > < / r-cell > < r-cell span = "2-10" > OS1/2 single-mode APC with a green plug< / r-cell >
< / r-grid >
< / r-cell >
< r-cell >
< r-grid columns = "10" class = "panel" id = "sfp" >
<!-- Module speeds -->
< r-cell span = "1-5" > < h2 > SFP< / h2 > < / r-cell >
< r-cell span = "6-10" > < h2 > SFP+< / h2 > < / r-cell >
< r-cell span = "1-5" > SFP 1 GbE< / r-cell >
< r-cell span = "6-10" > SFP+ 10 GbE< / r-cell >
< r-cell span = "1-5" > SFP28 25 GbE< / r-cell >
< r-cell span = "6-10" > QSFP+ 40 GbE< / r-cell >
< r-cell span = "1-5" > SFP56 50 GbE< / r-cell >
< r-cell span = "6-10" > QSFP28 100 GbE< / r-cell >
< r-cell span = "6-10" > QSFP56 200 GbE< / r-cell >
< r-cell span = "6-10" > QSFP-DD 400 GbE< / r-cell >
< / r-grid >
< / r-cell >
< r-cell >
< r-grid columns = "1" class = "panel" id = "bgp" >
< h2 > BGP Table path selection< / h2 >
< p > Prefer the highest local-preference value.< br >
Prefer the shortest AS-path length.< br >
Prefer the lowest origin value.< br >
Prefer the lowest MED value.< br >
Prefer routes learned from an EBGP peer over an IBGP peer.< br >
Prefer best exit from AS.< br >
For EBGP-received routes, prefer the current active route.< br >
Prefer routes from the peer with the lowest Router ID.< br >
Prefer paths with the shortest cluster length.< br >
Prefer routes from the peer with the lowest peer IP address.< / p >
< p > < a href = "https://tools.ietf.org/html/rfc4271" > source< / a > < / p >
< / r-grid >
< / r-cell >
< r-cell class = "footer" >
< p > Provided by < a href = "https://tuxstash.de" > tuxstash.de< / a > < / p >
< / r-cell >
< / r-grid >
< / body >
< / html >